http://afs.sagepub.com/ Armed Forces & Society http://afs.sagepub.com/content/37/1/119 The online version of this article can be found at: DOI: 10.1177/0095327X09358651 2011 37: 119 originally published online 20 January 2010 Armed Forces & Society Jeffrey Pickering 2001 -- and the Use of Military Force, 1946 Dangerous Drafts? A Time-Series, Cross-National Analysis of Conscription Published by: http://www.sagepublications.com On behalf of: Inter-University Seminar on Armed Forces and Society can be found at: Armed Forces & Society Additional services and information for http://afs.sagepub.com/cgi/alerts Email Alerts: http://afs.sagepub.com/subscriptions Subscriptions: http://www.sagepub.com/journalsReprints.nav Reprints: http://www.sagepub.com/journalsPermissions.nav Permissions: http://afs.sagepub.com/content/37/1/119.refs.html Citations: by guest on March 27, 2011 afs.sagepub.com Downloaded from
Transcript
http://afs.sagepub.com/Armed Forces & Society
http://afs.sagepub.com/content/37/1/119The online version of this article can be found at:
DOI: 10.1177/0095327X09358651 2011 37: 119 originally published online 20 January 2010Armed Forces & Society
Jeffrey Pickering2001−−and the Use of Military Force, 1946
Dangerous Drafts? A Time-Series, Cross-National Analysis of Conscription
Published by:
http://www.sagepublications.com
On behalf of:
Inter-University Seminar on Armed Forces and Society
can be found at:Armed Forces & SocietyAdditional services and information for
Dangerous Drafts? A Time-Series, Cross-National Analysis of Conscription and the Use of Military Force, 1946 – 2001
Jeffrey Pickering 1
Abstract
Conscription has been claimed to both increase leaders’ propensity to use military force abroad and constrain them from doing so. The author sheds new light on this longstanding controversy by presenting the first time-series, cross-national quantitative analysis of the impact that state military manpower systems (either conscription or volunteerism) have on the initiation of both traditional, belligerent military missions and “operations other than war” (OOTWs). Using negative binomial regression on 166 states from 1946 to 2001, the author finds that states with conscript militaries have a significantly higher propensity to use belligerent military force than states with volunteer armies. Countries that practice conscription are also more likely than countries with volunteer forces to launch a specific type of OOTW, military operations against nonstate actors such as rebels or terrorists. Neither form of military manpower system seems, however, to be significantly related to the initiation of humanitarian military operations.
Keywords
conscription , draft , all-volunteer force , use of military force
In the first few years after 9/11, debate about the relative merits of conscription briefly returned to the U.S. national scene. It was a rare example of an issue that crossed party lines in contemporary American politics, with prominent Democrats and Republicans
AFS358651 AFS
1 Kansas State University, Manhattan, KS
Corresponding Author: Jeffrey Pickering, Kansas State University, Department of Political Science, Waters Hall 244, Manhattan, KS 66506 Email: [email protected]
by guest on March 27, 2011afs.sagepub.comDownloaded from
both supporting and opposing the return of the draft. 1 Although many arguments have been given in support of conscript and all-volunteer militaries, much attention has focused on the relationship these military manpower systems (MMSs) might have with the president’s ability to use military force overseas. Perhaps the most interest has been generated by U.S. representative Charles Rangel’s repeated attempts to reinsti-tute the draft as a way to constrain the president’s ability to launch inadvisable foreign military adventures. He maintains that military service spread across a wide segment of society that includes the political and business elite would give the president and Congress reason to pause before dispatching troops abroad on dangerous missions. As Rangel puts it, “Decision-makers . . . would more readily feel the pain of conflict and appreciate the sacrifice of those on the front lines if their children were there too.” 2
This article puts Rangel’s contention to an empirical test. To date, only two studies analyze arguments about MMSs and the use of military force using large- N , quantita-tive methods. 3 Unfortunately, these articles reach opposite conclusions. They also fail to analyze the full range of overt missions on which leaders can dispatch the military. 4 They study only military operations that directly challenge a target government or its policies, a phenomenon often termed dyadic force. They do not analyze missions that have sometimes been collectively referred to as “operations other than war” (OOTWs) and that have been growing increasingly prevalent over recent decades. OOTWs include operations for humanitarian purposes, to stabilize postconflict societies, and to target nonstate actors that employ nonconventional military means. 5 This article employs a newly updated data set to quantitatively analyze the impact that MMSs have on decision makers’ propensity to use either traditional, dyadic military force or OOTWs from 1946 to 2001. By doing so, it provides a fresh, and arguably more com-prehensive, analysis of an important, policy relevant question. It also offers the first large- N study of the subject that extends into the post – cold war period.
My article proceeds in five sections. The next section outlines extant arguments on the effect that MMSs have on the use of military force abroad and provides my hypoth-eses. The third section reviews the empirical literature on the topic, while the fourth outlines my research design. Empirical findings for both traditional military opera-tions and OOTWs are presented in the fifth section, and conclusions follow in the final section.
MMSs and the Use of Military Force The argument that conscription constrains leaders from dispatching troops on military missions is well established in democratic thought. This line of reasoning stretches back at least until the time of Kant, who argues in “Perpetual Peace” that standing armies, which in modern terms equate with all-volunteer forces (AVFs), are a “cause of offensive war” because they are not representative of the population. 6 When the population has broad representation in the armed forces, citizens in a republic will, in Kant’s words, be “very cautious” about using military force for fear of “decreeing for themselves all of the calamities of war.” 7
by guest on March 27, 2011afs.sagepub.comDownloaded from
Kant’s argument can be expanded beyond republics and their modern democratic equivalents. To the extent that the draft calls up young men and women from politi-cally important groups within society, it has the potential to act as a brake on any leader’s foreign military ventures. After all, even the most ruthless autocrats depend on elite constituencies to retain power. 8 Many despots in personalist regimes, in fact, use the armed forces as a form of patronage by appointing members of the ruling clique or their children to prestigious positions within the military. 9 It could thus be argued that decision makers will be wary of using military force in any political sys-tem where elite segments of society have to bear some of the costs of interstate conflict.
Conscription may not only constrain today’s leaders from using military force overseas but also bring a new generation of leaders to power that are cautious about using the military as a foreign policy tool. The number of veterans who serve in politi-cal office will tend to increase in the years following an introduction of the draft, and those who have donned the uniform tend to be more keenly aware of the potential human costs and the uncertainties associated with military operations than those who have not. 10
Scholars and policy makers who maintain that the draft tends to restrain decision makers believe that a volunteer military has the opposite effect. Since AVFs are typi-cally drawn from the less privileged in society and volunteers are well aware of the conditions of their service, political leaders have little reason to fear a political back-lash when they deploy them. 11 Leaders may also be more prone to use volunteer forces than conscripts because they have more confidence in their skills and their training. 12 AVFs typically have higher retention rates than conscript militaries, which results in a higher proportion of soldiers who have combat experience and who have had time to hone their craft. Extended periods of service may be an especially important determi-nant of military readiness in today’s specialized, high-tech militaries.
Although it did not receive as much attention in political debates when the issue of conscription resurfaced in the early 2000s, a compelling counterargument to this per-spective has nearly as distinguished a pedigree. For at least a century, it has been argued that the “ready supply of manpower” associated with conscript armies provides policy makers with opportunities to use foreign military force that typically smaller volunteer forces do not. 13 Woodrow Wilson espoused this view during the Versailles peace talks, although it was perhaps put best at the time by South African Premier Jan Smuts who asserted that “conscription is the taproot of militarism and war.” 14 This view echoes to this day. Steven Morse, of the Central Committee for Conscientious Objectors in the United States, states bluntly that “the purpose of the draft is, and has always been, to serve an expanding militarism and to provide cannon fodder to do that.” 15 Advocates of this view thus contend that conscript armies, not volunteer forces, tend to be correlated with an increased use of military force by states.
Empirical evidence supporting this argument can be traced back at least to the 1960s when Leonard Berkowitz advanced his well-known theory on aggressive cues. 16 Berkowitz found that individuals who are ready or “primed” to respond aggressively
by guest on March 27, 2011afs.sagepub.comDownloaded from
are more likely to react to cues in the environment in a series of experimental studies. Certain conditions lead to this readiness to act aggressively. For individuals, Berkow-itz noted that being caught in unpleasant situations such as experiencing pain, heat, or noise can prime individuals for aggression. Extrapolating this idea to collective group-ings of national decision makers, it might be argued that a large, well-prepared stand-ing army can serve a priming function by increasing the likelihood that decision makers will respond to negative external stimuli, or aggressive cues, with military force.
Proponents of this view also challenge two claims advanced by those asserting that the draft limits decision makers’ ability to dispatch troops overseas. First, they main-tain that veterans in positions of political power often tend to be more, not less, willing to use military force than policy makers who have no military background. 17 As Choi and James put it, this perspective contends that “since military leaders are what Lass-well called ‘specialists on violence,’ they have a lower average level of aversion for interstate war than do civilian leaders.” 18
Second, they dispute the claim that AVFs tend to be more battle ready than con-scripts. Proponents of this view argue that decision makers will have concerns about using AVFs because, as Marlowe observes, “the marketplace is an intermittent and insecure source for the quality of soldier needed in future wars.” 19 During certain periods of time, such as when the economy is struggling or national morale is high, all-volunteer militaries may have little difficulty recruiting soldiers of a high caliber. At other times, however, it may be hard to enlist the types of soldiers needed on the modern high-tech battlefield. 20
The evolution of the U.S. AVF provides an example. The U.S. military had great difficulty finding high-quality recruits in the 1970s, the decade the AVF was created. Partially as a result, U.S. armed forces were rife with drug and discipline problems by the late 1970s, and various measures of combat effectiveness declined sharply. This trend was reversed in the early 1980s when the U.S. military began to draw in more than enough high-quality recruits, as measured by high school graduation rates and Armed Forces Qualification Test scores. 21 The quality of U.S. military recruits remained high through the mid-1990s but began to erode in the late 1990s and early 2000s before rebounding again late in the decade in the midst of a historic recession. 22 In contrast, draft armies have the potential to consistently draw in talented individuals from all socioeducational levels of society, ensuring that the armed forces have ade-quate numbers of intelligent, capable soldiers for the modern battlefield. 23 Leaders may consequently be more confident about deploying draft militaries than AVF, which may result in the former being used more frequently than the latter.
A related argument asserts that volunteer soldiers may lack motivation to fight for their country. While there can be little doubt that many soldiers join the military out of patriotism and a sense of duty to their country, a good proportion may enlist because it is the best economic opportunity available to them. For recruits who fall in the latter category, the military is merely a way to improve their career prospects. Having indi-viduals who enlist for economic gain or because “of consumerism, even hedonism”
by guest on March 27, 2011afs.sagepub.comDownloaded from
form the backbone of the military may give leaders contemplating the use of force abroad pause. 24 Questions may be raised about the willingness of such individuals to fulfill their duties under fire, no matter whether these duties involve traditional combat or OOTWs. A different set of questions may, of course, be raised about the motivation and the patriotism of draftees.
Since both of these conflicting viewpoints cannot be equally valid, my hypotheses assume that a positive relationship exists between conscription and the use of military force abroad, either for traditional, belligerent missions that challenge target govern-ments or for OOTWs. 25 If the empirical evidence supports my hypotheses, it will lend credence to those who claim that draft armies are more readily deployed by decision makers than are volunteer forces. If the findings contradict my hypotheses, those asserting that decision makers find it easier to deploy AVFs will gain empirical back-ing. Either way, my results will shed new light on well-worn arguments about MMSs and the use of foreign military force.
My two hypotheses are the following:
Hypothesis 1: States with conscript militaries are more likely to initiate military missions that are hostile to target governments than states with volunteer militaries.
Hypothesis 2: States with conscript militaries are more likely to initiate OOTWs than states with volunteer militaries.
Previous Research Most empirical studies on MMSs focus on the factors that cause decision makers to implement one system over the other rather than the consequences of their choice. For example, a series of articles by economists in the late 1960s and early 1970s compared the economic viability of volunteer and conscript armies, with a consensus maintain-ing that volunteer militaries are superior to conscript armies because of greater eco-nomic efficiency and lower social costs. 26 Two economic studies in the early 1990s reached the opposite conclusion, however. 27
The first large- N empirical study of MMSs and the use of armed force abroad is Choi and James. 28 Although their article is designed to answer questions about the dyadic democratic peace rather than the more general category of foreign military force, they provide considerable insight on the latter subject. They find that countries with conscript armies were significantly more likely to be involved in dyadic milita-rized interstate disputes from 1886 to 1992 than countries with AVF, which leads them to conclude that MMSs should be added to the retinue of variables that help to explain the dyadic democratic peace.
Although Vasquez does not analyze the use of foreign military force as his depen-dent variable, his findings contradict those of Choi and James. 29 Vasquez focuses on the number of casualties that democratic militaries tend to suffer when they have either conscript or volunteer militaries. After controlling for the number of conflicts a
by guest on March 27, 2011afs.sagepub.comDownloaded from
state is involved in and other factors that might be related to casualty rates, he finds that from 1950 to 1985 volunteer militaries endured 30 percent more casualties than conscript militaries in democracies. Since conscript militaries tend to be larger than AVFs, 30 other things being equal, this leads him to surmise that democratic leaders are more tolerant of casualties among AVFs than they are of casualties among conscript forces. Following this logic further, Vasquez concludes that decision makers tend to have fewer reservations about deploying AVFs in combat situations than draft forces. AVFs thus “free leaders to act military.” 31
Both of these studies are pathbreaking in that they offer valuable insight into the long-neglected study of MMSs and the use of foreign military force, but more than their conflicting findings suggest that the topic deserves further research. The dyadic orientation of both articles raises questions about the scope of the knowledge they provide on the subject. 32 Among others, Fordham and Sarver have demonstrated that dyadic studies do not offer adequate insight into the factors that lead policy makers to use foreign military force. 33 The central problem with using dyadic analyses to study foreign military force is that they do not account for the full range of military missions initiated by states because not all military operations directly challenge other state governments.
Over the past half-century especially, an increasing number of foreign military operations have targeted nonstate actors such as rebel groups, insurgents, and terror-ists. Examples include Turkish interventions against Kurdistan Workers Party (PKK) strongholds in northern Iraq beginning in 1983 and growing increasingly common in the 1990s, periodic Israeli military actions against Hezbollah and other nonstate actors in Lebanon beginning in 1965, and various operations by Western militaries against Al Qaeda and other terrorist organizations since at least the mid-1990s. 34 Data from the International Military Intervention (IMI) database demonstrate that these cases are not anomalies. 35 Of the foreign military interventions recorded in IMI from 1946 to 2001, 29 percent have nonstate actors as targets. A further 30 percent are considered to be neutral toward the target government and thus would not be included in conventional dyadic studies of military force. Missions targeting nontraditional actors (i.e., those that are not other state governments) thus constitute a significant proportion of the cross-border military force that has been employed by state actors over the past half-century. As the examples above illustrate, for many states these missions are as politi-cally and strategically important as more traditional dyadic military force used against other state governments.
Since dyadic studies exclude this important category of foreign military force, they do not provide a complete account of the influences that compel decision makers to use military force abroad. They explain only the factors that lead decision makers to use one particular type of foreign military force, which represents a subset of the larger population of cases. This study attempts to improve our understanding of the relationship between MMSs and the use of military force abroad with the first large- N , cross-national analysis to evaluate both the belligerent missions targeting state gov-ernments common to dyadic studies and OOTWs.
by guest on March 27, 2011afs.sagepub.comDownloaded from
I employ a time-series, cross-sectional (TSCS) design of 166 countries from 1946 to 2001. The temporal coverage of the design is a product of data availability. Data for my dependent variables begin in 1946, and information on many of my control vari-ables ends in 2001. 36
Dependent Variables I use the IMI data set to operationalize the use of unilateral foreign military force. 37 IMI records the “movement of regular troops or forces of one country into the territory or territorial waters of another country . . . in the context of some political issue or dispute.” 38 In the IMI conceptualization, the single most important characteristic of unilateral foreign military intervention is political authorization at the national level. Foreign military intervention is considered first and foremost to be a policy tool, which is the result of a conscious decision by national leaders. The IMI database con-sequently excludes soldiers concentrated in foreign bases, in transit, on leave, or trans-porting materials. It also omits troops on training missions and military advisors unless they are involved in active combat. 39 The events cataloged in IMI thus correspond well with common conceptions of the use of military force abroad. 40
The breadth of the IMI conceptualization allows researchers to analyze the subset of foreign military activity most pertinent to their research question. 41 I focus on mili-tary operations with one thousand or more intervening troops. Decision makers will often not have to consider the quality or the socioeconomic makeup of the full comple-ment of the country’s armed forces when deciding to launch small-scale operations with fewer than one thousand soldiers. 42 I also use a six-category IMI variable labeled intervention direction to distinguish belligerent military missions, the traditional focus of the empirical literature, from OOTWs. The original six-part variable is coded 0 if the intervention neither directly supports nor opposes the target government. It is coded 1 if the intervention is intended to support the target government, 2 if it opposes rebels or opposition groups, 3 if it is intended to oppose the target government, 4 if it supports rebel or opposition groups, 5 if it supports or opposes a third-party govern-ment, and 6 if it supports or opposes rebel groups in a sanctuary. Since traditional, belligerent military missions are designed to challenge target governments , interven-tions coded 3 or 4 on the direction variable are used to delineate this type of force. 43 OOTWs are best captured by missions coded 0, 5, or 6. Since some OOTWs, such as relief operations, might be construed as supportive of the target government, I care-fully examined cases coded 1 or 2 on the intervention direction variable and added a handful of cases from these categories to my catalog of OOTWs.
In addition, since OOTWs cover a wide range of military missions and remain broadly defined, I use an additional set of IMI variables to further refine my categori-zation of OOTW. IMI includes nine “motivation” variables that attempt to capture the issues that cause state leaders to use military force. These motivation variables
by guest on March 27, 2011afs.sagepub.comDownloaded from
encompass the usual culprits, such as territorial disputes, economic incentives, and strategic concerns. 44 Of most interest for OOTWs are variables coding foreign mili-tary interventions launched for humanitarian purposes or against nonstate actors such as rebels or terrorist groups. Although both of these activities represent archetypical OOTWs, they are substantially different types of missions. Humanitarian missions involve troops delivering supplies, services, and/or policing functions rather than engaging in combat. Operations that target nonstate actors such as rebels or terrorist groups involve combat but usually highly asymmetrical, nonconventional fighting that is not intended to challenge the target state’s government. In my sample of OOTW, fully 93 percent of the cases are coded either nonstate operations (68 percent) or humanitarian operations (25 percent). To develop more precise knowledge on MMSs and the initiation of OOTWs, supplemental estimates are presented on these two dis-tinct forms of OOTWs.
My final sample includes ninety-six hostile military operations and fifty-three OOTWs that include thirty-six nonstate operations and thirteen humanitarian mis-sions. 45 Since some actors launch multiple interventions in the same year, each depen-dent variable is operationalized as a count variable.
Independent Variable Conscription is a dichotomous variable coded 1 if the draft is enforced in a country and 0 if it is not. Data are taken from volumes by Horeman and Stolwijk and by Prasad and Smythe, the two most comprehensive resources for information on MMSs after 1945. 46
Control Variables I employ a standard set of control variables for the use of foreign military force. The first is the Correlates of War (COW) Composite Index of Military Capabilities (CINC), termed capabilities in this study for brevity. CINC includes information on six vari-ables: energy consumption, iron and steel production, military expenditure, military personnel, total population, and urban population. The CINC index is produced by converting state-year data for each of these variables into the country’s share in the international system in a given year and then averaging across the six variables for each state-year. Since CINC capabilities scores have been found to be positively related to the use of military force in a wide number of quantitative studies of interna-tional conflict, I expect capabilities to be positively related to state use of military force in both belligerent operations and OOTWs. 47
My second control variable captures the acting state’s regime type. Polity score is operationalized with the polity2 variable in the Polity IV data set. 48 A widely used measure of democratization in the quantitative international conflict literature, 49 pol-ity2 subtracts a state’s autocracy score from its democracy score to create an index ranging from − 10 to +10. The Polity IV democracy index includes four components: openness of executive recruitment, competitiveness of executive recruitment,
by guest on March 27, 2011afs.sagepub.comDownloaded from
competitiveness of participation, and legislative constraints on the executive. The autocracy index includes all of the components of the democracy index plus one addi-tional one, the regulation of participation. Since higher values on my control variable polity score indicate that countries are becoming more democratic, these states may have somewhat less of a tendency to initiate belligerent military force. 50 It is more difficult to speculate on how changes in polity score affect OOTWs.
My third control variable is troop quality , which provides an indication of how well funded and presumably well trained a country’s military forces are. It divides COW data for annual military expenditures by COW data on the number of military person-nel in a country. Following Vasquez’s study previously discussed, Reiter and Stam, and others, I assume that decision makers with high-quality soldiers stand more chance of dispatching them on belligerent missions or OOTWs than counterparts with low-quality troops. 51 Of course, I also realize that this presumed general relationship will not hold in all cases. A number of historical states with limited military budgets have deployed extremely well-trained, high-quality soldiers. Some leaders may be perfectly happy to dispatch soldiers with low levels of readiness as well. War and civil war are binary variables that also use information from COW. They are coded 1 if a state was involved in a war or a civil war in a given year. It is conceivable that involvement in a war or a civil war may preclude decision makers from dispatching troops on additional belligerent operations or OOTW. 52 At the same time, given the contagion affects of armed conflict, involvement in internal or external wars could also prompt decision makers to dispatch troops into countries neighboring the war zone to combat forces loyal to their enemies. 53 Since COW data on interstate and intrastate wars end in 1997, I extend my data using Armed Conflict Database information on these two phenom-ena. 54 Finally, regional crisis counts the number of crises that occur in an actor’s region annually using the International Crisis Behavior data set. 55 Regional crises should increase the probability that decision makers will use belligerent force or OOTW. Along with war and civil war, regional crisis also helps to control for the selection effects that may characterize decisions to use foreign military force. 56
Statistical Methods Dispersion α scores indicate that negative binomial regression will provide the best estimates of my count dependent variables. 57 Three methodological issues are raised when using a negative binomial TSCS design. First, the aggregation of data into annual units may produce instances in time t when dependent variable events precede independent variable events such as implementing or rescinding conscription. I conse-quently lag my independent variable and control variables one year. Second, autocor-relation is common in TSCS count data. To control for it, I include lagged dependent variables ( t − 1) in each of my estimates. Since concerns have been raised about the inclusion of lagged dependent variables with heavy trending in TSCS analyses, I ran supplemental estimates of each of my models omitting the lagged dependent vari-able. 58 The results were substantively the same. Third, multicollinearity is a potential
by guest on March 27, 2011afs.sagepub.comDownloaded from
concern in any multivariate regression. I assessed all estimates with variance inflation factor (VIF) tests. VIF scores for individual variables never exceed 2, indicating that multicollinearity does not represent a problem in these estimates.
Reviewing the Empirical Evidence Table 1 presents my findings on belligerent intervention and OOTWs. The model χ 2 outcomes for both models suggest that they fit reasonably well. The most notable find-ing from Table 1 is the support it lends to hypothesis 1. From 1946 to 2001, states with conscript militaries had a significantly higher probability of initiating belligerent mili-tary interventions than did states with volunteer forces. This outcome is statistically significant at the .05 level in a one-tailed test, holding control variables such as democ-racy level constant.
I ran a number of supplemental estimates to determine the temporal boundaries of my outcomes and to test their robustness. I broke my sample into cold war (1946 – 89) and post – cold war (1990 – 2001) subsamples to see if the results for conscription hold across both periods. They do. I also substituted the COW military personnel variable
Table 1. Time-Series, Cross-Sectional Negative Binomial of Belligerent Foreign Military Intervention and Operations other than War (OOTWs)
for capabilities and troop quality to determine if my findings were being driven by variations in size between conscript and volunteer armies. Military personnel provides an annual count of the number of men and women who are active in a country’s uni-formed military. 59 The statistical significance of conscription does not diminish with the inclusion of this direct measure of military size. It may be that decision makers are prone to use conscript armies not because they are large but because they, as Choi and James state, “provide quicker and higher military readiness or preparedness than all-volunteer forces.” 60
The substantive impact of conscription is considerable. When other variables in the model are held at their means, the predicted probability that a state with conscription will use belligerent military force is 58 percent higher than the probability that a state without the draft will use belligerent force. Conscription’s substantive effect is com-parable to that of full-scale war, undoubtedly a phenomenon with the potential to alter a state’s propensity to use hostile military force in other theaters. In my sample involvement in an ongoing war reduces the likelihood an actor will use belligerent military force against another state by 65 percent. Not surprisingly, however, state capabilities have the strongest impact on belligerent intervention. A one standard devi-ation increase (0.26) in a state’s capability score from the sample mean (0.008) raises the probability of using belligerent military force by 123 percent.
Conscription is statistically significant in my estimate of OOTWs in Table 1 as well, but only at the .10 level. This outcome lends initial support to hypothesis 2, which states that countries with draft armies are more likely to initiate OOTW than countries with AVFs. This finding also remains consistent in supplemental estimates that analyze cold war and post – cold war subsamples and that include military person-nel as a control variable. Holding other variables in the estimate at their means or medians, countries with conscript armies are 39 percent more likely to launch OOTWs than states with AVFs. However, since OOTW is a broad classification that arguably encompasses conceptually distinct forms of military force, this relationship requires further investigation.
My control variables in Table 1 are all in the appropriate direction. The negative, statistically significant coefficient for war in my belligerent intervention model coupled with the positive, statistically significant coefficients for war and civil war in my OOTW model are of particular interest. These findings suggest that actors involved in wars tend not to initiate additional hostile military actions against other states, but they are prone to use military force against nonstate actors (militias, rebel groups) in neigh-boring countries that are aligned with their foes. U.S. attacks on Vietcong positions in Cambodia during the Vietnam War offer one well-known example. Ethiopian opera-tions against militia members that took harbor in Somalia during the 1998 – 2000 Eritrean – Ethiopian War provide an illustration of one of the many less publicized cases.
Table 2 sheds new light on the relationship between MMSs and OOTWs by sepa-rating out the two most prominent types of foreign military force included in the OOTW category, operations against nonstate actors and humanitarian missions. The utility of breaking OOTWs down into more precise categories is immediately
by guest on March 27, 2011afs.sagepub.comDownloaded from
apparent. While conscription is positive and statistically significant in the estimate of nonstate operations, it does not even approach statistical significance in the estimate of humanitarian operations. These findings remain consistent across cold war and post – cold war subsamples. 61
The substantive impact conscription has on nonstate operations is sizeable. Coun-tries with the draft have a 227 percent higher probability of using military force against nonstate actors than countries with AVFs, holding other variables at their means from 1946 to 2001. Perhaps conscript armies’ preparedness influences decisions to use force against nonstate actors as well as state governments. Operations against rebels or terrorist groups can, after all, be as challenging and lethal as the use of traditional, dyadic military force.
The fact that conscription is statistically insignificant in the estimate of humanitar-ian interventions is as enlightening as the statistically significant finding in the non-state actor model. There may be a number of theoretical explanations for this nonfinding. One is the casualty sensitivity that typically accompanies the use of mili-tary force for humanitarian missions. There is a good deal of evidence that decision
Table 2. Time-Series, Cross-Sectional Negative Binomial of Nonstate and Humanitarian Interventions
Note: Standard errors are in parentheses below the estimates. Civil war and the lagged dependent vari-able are dropped from the estimate of humanitarian operations because they predict failure perfectly. * p < .10, one-tailed. ** p < .05, one-tailed. *** p < .01, one-tailed.
by guest on March 27, 2011afs.sagepub.comDownloaded from
makers launch humanitarian operations only when they believe that the costs of the operation will be low, particularly with regard to their soldiers’ lives. 62 Wheeler notes that Western governments and publics, at least, have a “strong reluctance . . . to plac-ing their soldiers in harm’s way” during these types of missions. 63 In part because of this sensitivity to casualties and other costs, many cold war and even post – cold war humanitarian interventions were initiated only when logistics allowed for safe deploy-ments and when consent about the need for an external intervention existed among key political actors in the target state. 64 Given this context, it is understandable why decision makers might not give too much consideration to the country’s MMSs when deploying troops on humanitarian missions. Since decision makers often presume that their armed forces will not be tested in any serious way during these deployments, they do not weigh considerations of troop quality or troop readiness heavily when they initiate these operations.
Added to this, many post – cold war humanitarian interventions have been multi-lateral actions, which help to diffuse accountability for the mission’s outcome. 65 As a result, some participating states may tend to “free ride” by not providing either their best troops or a sufficient number of troops. 66 When troop readiness and suc-cessful mission outcomes are not crucial in decisions to dispatch soldiers abroad, decision makers have little reason to consider the impact that MMSs may have on mission performance and ultimately on decisions about whether or not to send troops.
Control variable outcomes also vary across the two types of OOTW estimated in Table 2 . Most of the control variable results are intuitive, such as the powerful influ-ence capabilities have on the initiation of both types of missions. Two are not, how-ever. The insignificance of troop quality in the estimate of nonstate operations was not expected and may reflect the limitations of this control variable. Although it is com-mon in the quantitative conflict literature, Biddle contends that measures such as troop quality are too crude to adequately capture military preparedness. 67 War’s positive, statistically significant relationship with humanitarian operations was also unantici-pated. Since my control variables are lagged, this finding appears to be driven by the 1992 Somalia relief operations that were undertaken by some of the same actors that participated in the coalition war against Iraq in 1991. Both of these relationships deserve future empirical scrutiny, however.
Conclusions My results suggest that Vasquez is correct to assert that “quantitative IR scholars would benefit from examining not just states’ material capabilities and weapons, but also their MMSs, which may constrain or facilitate their ability to use force.” 68 In the first large- N test of the relationship between MMSs and the initiation of both belliger-ent military force and OOTWs, I find that decision makers with conscript armies were significantly more prone to use military force against both state and nonstate actors than counterparts with volunteer militaries from 1946 to 2001. When this result is
by guest on March 27, 2011afs.sagepub.comDownloaded from
added to Choi and James’s publications and Vasquez’s article, it seems increasingly evident that the empirical literature on conflict has neglected an important causal vari-able for too long. 69 MMSs appear to be a significant part of the explanation of the use of foreign military force.
While this study should help to improve future quantitative analyses of the use of military force overseas, I would urge caution before using the results of this research to inform policy makers or policy debates. Large- N statistical research has many advantages, with the most notable being the ability to incorporate a large number of cases over lengthy periods of time and to build generalizations across these cases. Such breadth comes at a price, however. The variables included in large- N studies will never capture all of the historical and contextual issues that help to shape different MMSs and that influence decisions to dispatch armed forces to other countries. Future case study research may be able to account for such complexities and to build on large- N analyses such as the one presented in this study. Until such in-depth research is completed for specific countries, however, this study’s findings can be considered to highlight only general tendencies. One cannot claim that they offer insight into dif-ferent countries’ propensities to use external military force or into the consequences associated with the adoption of different MMSs by specific states. In short, the results presented here provide a good deal of broad knowledge on the relationship between MMSs and the use of force, but additional research will be needed to refine our under-standing of this relationship.
Even with this important caveat, however, this study’s findings begin to cast some doubt on the claim that conscription constrains leaders from using military force abroad. This common argument contends that when the sons and daughters of promi-nent politicians and business leaders are drafted into the military, elites will be hesitant to send the country’s armed forces into harm’s way. Although this view has practically become conventional wisdom over recent years, it has yet to be tested in a large- N analysis that spans both cold war and post – cold war time periods. This study provides such a test and, in doing so, offers an initial challenge to this prevalent view. Hope-fully, in-depth, qualitative research that builds on large- N findings from this and future studies will begin to map out the ways that different MMSs affect policy makers’ deci-sions to use military force. Increasingly precise knowledge about the relationship between MMSs and the foreign policy decision-making process will, of course, be of more than just academic interest; it has the potential to benefit both military and civil-ian decision makers.
Acknowledgments
An earlier version of this article was presented at the 2009 annual meeting of International Studies Association in New York and at a seminar hosted by the Political Science Department at Oklahoma State University (OSU). I would like to thank the participants at the OSU seminar, editor Patricia Shields, and three anonymous reviewers for helpful suggestions that improved the article.
by guest on March 27, 2011afs.sagepub.comDownloaded from
The author declared no potential conflicts of interest with respect to the authorship and/or publication of this article.
Funding
The author wishes to thank the National Science Foundation for generous funding to update the International Military Intervention data used in this article (NSF Award SES-0518294, 2005).
Notes
1. For example, bills calling for reinstating some form of the draft were introduced both by Republicans and Democrats in the U.S. House of Representatives from 2001 to 2003. The Universal Military Training and Service Act of 2001 (HR 3598) was introduced by Republi-cans Nick Smith and Curt Weldon and was cosponsored by Republican Roscoe Bartlett. The Universal National Service Act of 2003 (HR 163) was introduced by Democrat Rangel in the House and by Democrat Fritz Hollings in the Senate (S 89). Senator Hagel was an outspoken Republican favoring reinstating some form of conscription at this time, while Representative Murtha (one of two Representatives to vote for HR 163) was a notable Democrat making relatively similar arguments. In contrast, Republican Representatives John J. Duncan and Ron Paul joined Democrats John Conyers, Jr., Cynthia McKinney, and others in cosponsoring H.CON.RES 368 in 2002 that explicitly opposed conscription. The nonpartisan character of this issue had largely evaporated by the time Rangel reintroduced the Universal National Service Act in 2006 and again in 2007. By that time, the bill had scant support and tended to be seen as a symbolic measure in opposition to the war in Iraq. Among others, see “Legisla-tive Background: Recent Action on Compulsory National Service,” Congressional Digest 85 (2006): 193-224.
2. “Legislative Background,” 206. 3. Seung-Whan Choi and Patrick James, “No Professional Soldiers, No Militarized Interstate
Disputes? A New Question for Neo-Kantianism,” Journal of Conflict Resolution 47 (2003): 796-816; Joseph Paul Vasquez III, “Shouldering the Soldiering: Democracy, Conscription, and Military Casualties,” Journal of Conflict Resolution 49 (2003): 849-73.
4. Fordham and Sarver spell out the conceptual problems associated with equating military force used against other state governments (dyadic force) with the more general category of state use of force, which can include actions against nonstate actors and various “friendly” uses of force such as humanitarian missions. Benjamin O. Fordham and Christopher C. Sarver, “Militarized Interstate Disputes and US Uses of Force,” International Studies Quar-
terly 45 (2001): 455-66. 5. Charles Moskos, “What Ails the All-Volunteer Force: An Institutional Perspective,” Param-
eters (Summer 2001): 29-47; Michael E. O’Hanlon, Defense Strategy for the Post-Saddam
Era (Washington, DC: Brookings Institution, 2005). 6. Immanuel Kant, Kant’s Political Writings , ed. Hans Reis, trans. H. B. Nesbit (Cambridge,
UK: Cambridge University Press, 1963), 94. 7. Ibid., 95.
by guest on March 27, 2011afs.sagepub.comDownloaded from
8. Mark J. Peceny and Caroline C. Beer, with Shannon Sanchez-Terry, “Dictatorial Peace?” American Political Science Review 96 (2002): 15-26.
9. See Barbara Geddes, “Stages of Development in Authoritarian Regimes,” in World Order
after Leninism , ed. Vladimir Tismaneanu, Marc M. Howard, and Rudra Sil (Seattle: Univer-sity of Washington Press, 2006), 161-63; and Barbara Geddes, Paradigms and Sand Cas-
tles: Theory Building and Research Design in Comparative Politics (Ann Arbor: University of Michigan Press, 2003). Geddes observes that in personalist dictatorships, rulers tend to politicize the military by recruiting elite political supporters into leadership positions within the military. These supporters may represent important political or ethnic groups within society. Furthermore, she finds that from 1945 to 1999 nearly half of all authoritarian regimes created by militaries or political parties were fully or partially personalized within three years of the regime’s creation. “Stages of Development,” 164. For an example of the personalization of an African military, see Kisangani N. F. Emizet, “Explaining the Rise and Fall of Military Regimes: Civil-Military Relations in the Congo,” Armed Forces & Society 26(2000): 203-27.
10. Samuel P. Huntington, The Soldier and the State: The Theory and Politics of Civil-Military
Relations (Cambridge, MA: Harvard University Press, 1957); Richard K. Betts, Soldiers,
Statesmen, and Cold War Crises (Cambridge, MA: Harvard University Press, 1977); Mor-ris Janowitz, “The Logic of National Service,” in The Military Draft: Selected Readings on
Conscription , ed. Martin Anderson and Barbara Honegger (Stanford, CA: Hoover Institu-tion Press, 1982); Peter D. Feaver and Christopher Gelpi, Choosing Your Battles: American
Civil-Military Relations and the Use of Force (Princeton, NJ: Princeton University Press, 2004).
11. Lawrence J. Korb, “Military Manpower Training Achievements and Challenges for the 1980s,” in The All-Volunteer Force after a Decade: Retrospect and Prospect , ed. William Bowman, Roger Little, and G. Thomas Sicilia (New York: Pergamon-Brassey’s, 1986); Seung-Whan Choi and Patrick James, Civil-Military Dynamics, Democracy, and Interna-
tional Conflict (New York: Palgrave, 2005); John Byron, “The Failure of the All-Volunteer Force,” Proceedings of the US Naval Institute 132 (2006): 12-14. The bulk of the literature on the U.S. all-volunteer force claims it is overwhelmingly made up of individuals from lower socioeconomic classes. See Moskos, “What Ails”; Vasquez, “Shouldering.” Bandow and O’Hanlon, however, argue that it may be more representative of U.S. society than is typically claimed. See O’Hanlon, Defense Strategy ; Doug Bandow, “Mend, Never End, the All-Volunteer Force,” Orbis 43 (2000): 463-75.
12. Bandow, “Mend, Never End.” 13. Ibid., 470; Choi and James, Civil-Military Dynamics . White finds that conscript armies are
on average 34 percent larger than volunteer armies after controlling for a number of factors that affect military size. Michael D. White, “Conscription and the Size of Armed Forces,” Social Science Quarterly 70 (1989): 772-81.
14. Denis Hayes, Conscription Conflict: The Conflict of Ideas in the Struggle for and against
Military Conscription in Britain between 1901 and 1939 (New York: Garland, 1973), 346. 15. Steven Morse, “Should the All-Volunteer Force Be Replaced by Universal, Mandatory
National Service?” Congressional Digest 85 (2006): 219.
by guest on March 27, 2011afs.sagepub.comDownloaded from
16. Leonard Berkowitz, Aggression: Its Causes, Consequences, and Control (Philadelphia: Temple University Press, 1993). I thank an anonymous reviewer for noting the relevance of Berkowitz’s ideas to this argument.
17. Roger W. Benjamin and Lewis J. Edinger, “Conditions for Military Control over Foreign Policy Decisions in Major States: A Historical Explanation,” Journal of Conflict Resolution 15 (1971): 5-31; Graham T. Allison, Albert Canesale, and Joseph S. Nye, Jr., Hawks, Doves,
and Owls: An Agenda for Avoiding Nuclear War (New York: Norton, 1985); Guy D. Whit-ten and Henry S. Bienen, “Political Violence and Time in Power,” Armed Forces & Society 23 (1996): 209-34; Julian Schofield, “Militarized Decision-Making for War in Pakistan, 1947 – 1971,” Armed Forces & Society 27 (2000): 131-48.
18. Seung-Whan Choi and Patrick James, “Civil-Military Relations in a Neo-Kantian World, 1886 – 1992,” Armed Forces & Society 30 (2004): 229.
19. David H. Marlowe, “The Manning of the Force and the Structure of Battle,” in ed., Conscripts and Volunteers , ed. Robert K. Fullinwider (Totowa, NJ: Rowman and Allan-held), 50.
20. Byron, “Failure”; Charles Moskos, “Should the AVF be Replaced by Universal, Mandatory National Service?” Congressional Digest 85 (2006): 220-22.
21. Bandow, “Mend, Never End”; James Fallows, “Why the Country Needs It,” in The Mili-
tary Draft , ed. Jason Berger (New York: H. W. Wilson, 1981), 75-82; John G. Kester, “The Reasons to Draft,” in The All-Volunteer Force After a Decade: Retrospect and
Prospect , ed. William Bowman, Roger Little, and G. Thomas Sicilia (New York: Pergamon-Brassey’s, 1986), 286-315. Moskos maintains that “there is clear relationship between socio-educational background and soldierly performance.” Charles Moskos, “National Service and the All-Volunteer Force,” in The Military Draft , ed. Jason Berger (New York: H. W. Wilson Company, 1981), 36. Also see Marlowe, “The Manning,” 50; Kester, “Reasons,” 295.
22. As measured by Armed Forces Qualification Test scores and high school graduation rates. Byron, “Failure”; Moskos, “Should the AVF be Replaced”; Ann Scott Tyson, “A Historic Success in Military Recruiting: In the Midst of Downturn, All Targets Are Met,” Washing-
ton Post , October 14, 2009. 23. Choi and James, “No Professional Soldiers,” 802. Fick takes the opposite view. Nathaniel
Fick, “A Draft Will Lower the Quality of the Military,” in Military Draft , ed. George Milite (New York: Greenhaven, 2007), 36-42.
24. Charles Moskos, “The Marketplace All Volunteer Force: A Critique,” in The All-Volunteer
Force after a Decade: Retrospect and Prospect , ed. William Bowman, Roger Little, and G. Thomas Sicilia (New York: Pergamon-Brassey’s, 1986), 17; Choi and James, “No Profes-sional Soldiers.”
25. This article does not directly address the possibility that there may be a reciprocal relation-ship between conscription and interstate conflict. In other words, it is theoretically possible that conscription leads to a higher propensity to become involved in interstate conflict and that involvement in interstate conflict simultaneously tends to increase decision makers’ proclivity to implement conscription. To increase confidence that causality does in fact run from military manpower systems (MMSs) to the use of force, I ran all of my statistical
by guest on March 27, 2011afs.sagepub.comDownloaded from
estimates after lagging my independent variable conscription two and then five years. The substance of my findings remains the same.
26. W. Lee Hansen and Burton A. Weisbrod, “Economics of the Military Draft,” Quarterly
Journal of Economics 81 (1967): 395-421; Milton Friedman, An Economist’s Protest: Col-
umns in Political Economy (Glen Ridge, NJ: Thomas Horton, 1972). 27. Dwight R. Lee and Richard B. McKenzie, “Re-examination of the Relative Efficiency of
the Draft and the All-Volunteer Force,” Southern Economic Journal 58 (1992): 644-54; John T. Warner and Beth J. Asch, “The Economics of Military Manpower,” in Handbook
of Defense Economics , ed. Keith Hartley and Todd Sandler (Amsterdam: Elsevier, 1995), 347-98.
28. Choi and James, “No Professional Soldiers.” 29. Vasquez, “Shouldering”; Choi and James, “No Professional Soldiers.” 30. White, “Conscription.” 31. Vasquez, “Shouldering,” 870. Research on the long-term impact that MMSs have on the use
of force is similarly divided. Feaver and Gelpi find that the U.S. propensity to initiate mili-tarized interstate disputes (MIDs) declined significantly when the number of veterans in the U.S. Congress increased during the period 1816 to 1992. Choi and James, however, reach the opposite conclusion in a cross-national study of MID involvement from 1886 to 1992. Feaver and Gelpi, Choosing Your Battles ; Choi and James, “Civil-Military Relations.”
32. Choi and James have limited utility for understanding state use of force for a second reason. They analyze MID involvement rather than MID initiation as their dependent variable. Decision makers can become involved with MIDs by being drawn into ongoing conflicts rather than consciously choosing to initiate armed force. Choi and James, “No Professional Soldiers.” Choi and James look specifically at MID initiation in a 2008 article, but again analyze only dyadic disputes. Seung-Whan Choi and Patrick James, “Civil-Military Struc-ture, Political Communication, and the Democratic Peace,” Journal of Peace Research 45 (2008): 37-53.
33. Fordham and Sarver, “Militarized Interstate Disputes.” 34. A host of other examples could be given, ranging from Chinese intervention into Burma
to attack Kuomintang troops active on the Chinese – Burmese border in 1951 to Rwandan military missions against Hutu militias operating in eastern Congo after 1994.
35. For further information on the International Military Intervention (IMI) database, see note 37. 36. Note that many former colonies enter my sample decades after 1946. After accounting for
these former colonies, there are still 1,096 missing observations in my sample. The bulk of these (726) are a result of missing information in my control variable troop quality. As a robustness check on my results, I removed this control variable and reran my estimates. The results were substantively the same.
37. On IMI see Jeffrey Pickering and Emizet F. Kisangani, “The International Military Inter-vention Data Set: An Updated Resource for Conflict Scholars,” Journal of Peace Research 46 (2009): 589-99; Frederic S. Pearson and Robert A. Baumann, “International Military Intervention, 1946 – 1988” (Inter-University Consortium for Political and Social Research [ICPSR], Data Collection 6035, University of Michigan, 1993); Emizet F. Kisangani and Jeffrey Pickering, “International Military Intervention, 1989 – 2005” (ICPSR, Data
by guest on March 27, 2011afs.sagepub.comDownloaded from
Collection 21282, 2008). Unilateral force is defined as a mission under the control of the nation’s military high command. Unilateral actions may be taken in coordination with other states’ armed forces. These operations are termed multilateral actions. In contrast, multi-national operations are missions where two or more states operate under the command of a single nation’s military high command or under the command of an international or regional organization. See Pickering and Kisangani, “International Military Intervention Data Set,” 593; Patrick Regan, Civil Wars and Foreign Powers: Outside Intervention in
Interstate Conflict (Ann Arbor: University of Michigan Press, 2002), 102) 38. Pearson and Baumann, “International Military Intervention,” iii. 39. IMI is an event data set on military intervention that records a wide range of information
on these incidents, from actors, targets, and initiation and termination dates to specific characteristics of military operations. As is common in international conflict events data, IMI codes a new event for each country that is targeted and for each actor intervening in the country, including multinational actors. For example, the U.S. use of force against Iraq in Kuwait in 1991 is coded as a separate event than the U.S. invasion of Iraq the same year. IMI also includes multinational operations against states, but these are not included in the present analysis. The data set does not aggregate multilateral uses of force. IMI includes 1,115 military interventions from 1946 to 2005. The present study examines large-scale military interventions with over one thousand intervening troops from 1946 to 2001.
40. For studies using IMI, among others see Mark J. Peceny, “Forcing Them to Be Free?” Polit-
ical Research Quarterly 52 (1999): 549-82; Dan Reiter, “Does Peace Nurture Democracy?” Journal of Politics 63 (2001): 935-48; Matthew Krain, “International Intervention and the Severity of Genocides,” International Studies Quarterly 49 (2005): 363-87; Emizet Kisan-gani and Jeffrey Pickering, “Diverting with Benevolent Military Force,” International Stud-
ies Quarterly 51 (2007): 277-300. 41. On the conceptual breadth of IMI, see Charles W. Kegley, Jr. and Margaret G. Hermann,
“Putting Military Intervention into the Democratic Peace: A Research Note,” Comparative
Political Studies 30 (1997): 81; Peceny, “Forcing Them,” 560. 42. Countries with both types of MMSs may also have highly trained “special” forces available
for smaller missions. On the one-thousand-soldier threshold for large-scale interventions, see Jeffrey Pickering and William R. Thompson, “Stability in a Fragmenting World: Inter-state Military Force, 1946 – 1988,” Political Research Quarterly 51 (1998): 241-63.
43. Among others, Krain, “International Intervention,” and Pickering and Thompson, “Stability in a Fragmenting World,” use the same operationalization of belligerent military force.
44. Diehl observes that IMI is relatively unique among quantitative conflict data sets in cod-ing contentious issues. His article on this topic, of course, predates Issue Correlates of War database. Paul F. Diehl, “What Are They Fighting For? The Importance of Issues in Inter-national Conflict Research,” Journal of Peace Research 29 (1992): 333-44.
45. The number of humanitarian missions is small because a large proportion of the humani-tarian operations in IMI are undertaken by international organizations such as the United Nations or the African Union. Also, many unilateral missions of this type include fewer than one thousand troops.
by guest on March 27, 2011afs.sagepub.comDownloaded from
46. See Choi and James, “No Professional Soldiers,” 803. Bart Horeman and Marc Stolwijk, eds., Refusing to Bear Arms: A World Survey of Conscription and Conscientious Objection
to Military Service (London: War Resister’s, 1998); Devi Prasad and Tony Smythe, eds., Conscription: A World Survey (London: War Resister’s, 1968). The annual Military Bal-
ance publication from the International Institute for Strategic Studies (Oxford, UK: Oxford University Press, 1970 – 2003) was used to cross-check these sources.
47. See J. David Singer, “Reconstructing the Correlates of War Dataset on Material Capabilities of States, 1981 – 1985,” International Interactions 14 (1987): 115-32; Scott D. Bennett and Allan Stam, “EUGene: A Conceptual Manual,” International Interactions 26 (2000): 179-204. Bennett and Stam describe a prominent computer program used to generate data sets for quantitative studies of international conflict. In doing so, they describe the most com-mon operationalizations of control variables used in the quantitative international conflict literature, including the operationalizations of capabilities, polity score, war, and civil war employed here.
48. Monty Marshall and Keith Jaggers, “Polity IV Project,” www.cidcm.umd.edu/polity (accessed November 12, 2007).
49. On the common practice of subtracting the Polity IV autocracy score from the democracy score in the quantitative literature, see, among others, Gretchen Casper and Claudiu Tufis, “Correlation versus Interchangeability: Empirical Findings on Democracy Using Highly Correlated Data Sets,” Political Analysis 11 (2003): 197-98. As a robustness check, I reran all of my statistical analyses with the 11-point Polity IV democracy index instead of polity2. The results were substantively the same.
50. Among others, see John MacMillan, “Beyond the Separate Democratic Peace,” Journal of
Peace Research 40 (2003): 233-43. 51. Vasquez, “Shouldering the Soldiering,” 860; Dan Reiter and Allan C. Stam, Democracies
at War (Princeton, NJ: Princeton University Press, 2002). 52. Among others, see Benjamin O. Fordham, “Another Look at Parties, Voters, and the Use of
Force Abroad,” Journal of Conflict Resolution 46 (2002): 572-96. 53. See Harvey Starr and Randolph M. Siverson, “Cumulation, Evaluation, and the Research Pro-
cess: Investigating the Diffusion of Conflict,” Journal of Peace Research 35 (1998): 231-37. 54. ACD version 3.0 (2004) was used since version 4.0 (2007) does not include war as a sepa-
rate category in the intensity variable. Håvard Strand, Lars Willhelmsen, and Nils Peter Gleditsch, “Armed Conflict Database,” version 3.0 (Oslo: International Peace Research Institute, 2004).
55. I employ Correlates of War’s (COW) standard demarcation of six regions: the Americas, country codes 1 – 199; Europe, country codes 200 – 399; Africa, country codes 400 – 599; the Middle East, country codes 700 – 899; and Oceania, country codes 900 – 999. A more nar-rowly defined categorization of subsystems based on regions in the International Crisis Behavior dataset was also used in supplemental analyses. The substantive results were simi-lar. Michael Brecher and Jonathan Wilkenfeld, A Study of Crisis (Ann Arbor: University of Michigan Press, 2000).
56. The following descriptive statistics summarizing my control variables include the mean, standard deviation, minimum, and maximum for each variable, respectively: capabilities:
by guest on March 27, 2011afs.sagepub.comDownloaded from
57. Since the use of military force is an uncommon phenomenon, I also employ zero-inflated negative binomial (ZINB) regressions to estimate my first two models (in Table 1 ). Since the substantive results for negative binomial and ZINB estimates are the same and various bayesian information criterion scores strongly favor the standard negative binomial regres-sions, I present results from my standard negative binomial estimates akaike information criterion scores comparing the two estimators were indeterminate. ZINB regressions would not converge for my last two models (in Table 2 ), presumably because of limited variation in the dependent variables. I converted these dependent variables to binary variables and estimated the models with relogit. Since my original negative binomial estimates, logit estimates, and relogit estimates are substantively the same, I present negative binomial regressions below.
58. Thomas Plümper, Vera E. Troeger, and Philp Manow, “Panel Data Analysis in Comparative Politics: Linking Theory to Method,” European Journal of Political Research 44 (2005): 327-54.
59. Since the COW military personnel variable is a component of both capabilities and troop quality, it cannot be included in the full estimate without generating high levels of multicol-linearity. In addition, since capabilities and troop quality are created with overlapping COW information, I ran them separately in each of my estimates in supplemental analyses with no change in the results. As noted above, variance inflation factor scores are uniformly low in my models even with the inclusion of both capabilities and troop quality.
60. Choi and James, “Civil-Military Relations,” 236. 61. I tested the robustness of each of the models in Tables 1 and 2 by identifying influential
cases in each model, removing them from my data, and rerunning the estimates. Pregibon D-Beta, deviance, Hosmer and Lemeshow Delta chi-squared, and Hosmer and Lemeshow Delta-D influence statistics were used to identify influential cases. For example, in my bel-ligerent intervention model in Table 1 , Libya’s intervention into Chad in 1979, Pakistan’s use of force in Afghanistan in 1989, and Somalia’s incursion into Ethiopia in 1977 were identified as influential cases. My independent variable conscription remains statistically significant after these cases are omitted from the estimate. Conscription’s z score actually increases from 1.77 to 2.03 when these variables are removed. Conscription retains its sta-tistical significance when influential cases are removed from the operations other than war ( Table 1 ) and nonstate operations ( Table 2 ) estimates as well.
62. See Nicholas J. Wheeler, “Introduction: The Political and Moral Limits of Western Military Intervention to Protect Civilians,” in The Dimensions of Western Military Intervention , ed. Colin McInnes and Nicholas J. Wheeler (Portland, OR: Frank Cass, 2002); William A. Boettcher III, “Military Intervention Decisions Regarding Humanitarian Crises,” Journal
of Conflict Resolution 48 (2004): 331-55. 63. Wheeler, “Introduction,” 7. 64. Andrea Kathryn Talentino, Military Intervention after the Cold War (Athens: Ohio
University Press, 2005), 282; Dominick Donald, “The Doctrine Gap: The Enduring Problem
by guest on March 27, 2011afs.sagepub.comDownloaded from
of Contemporary Peace Support Operations Thinking,” in The Dimensions of Western Mili-
tary Intervention , ed. Colin McInnes and Nicholas J. Wheeler (Portland, OR: Frank Cass, 2002), 107-39.
65. Pickering and Kisangani, “International Military Intervention Data Set,” 595. 66. See Boettcher, “Military Intervention Decisions”; and Joseph Lepgold, “NATO’s Post-Cold
War Collective Action Problem,” International Security 23 (1998): 78-106. 67. Stephen Biddle, Military Power: Explaining Victory and Defeat in Modern Battle (Princ-
eton, NJ: Princeton University Press, 2004). 68. Vasquez, “Shouldering,” 870. 69. Choi and James, “No Professional Soldiers”; Vasquez, “Shouldering.”
Bio
Jeffrey Pickering is professor and department head of political science at Kansas State University in Manhattan, KS.
by guest on March 27, 2011afs.sagepub.comDownloaded from
