Military Strategy Magazine - Volume 8, Issue 1

Volume 8, Issue 1, Summer 2022 29 jointly waging combat in the same operational battlespace. That is, in the hope of increasing their chances of military victory, they deploy their forces side-by-side with those fielded by a partner and the combined formation then works in concert at the operational and tactical levels of war to defeat the adversary in discrete battles. Battlefield coalitions have been a relatively common phenomenon since the turn of the twentieth century and are growing increasingly frequent. Examining new data that we have collected on 492 major battles fought during 62 interstatewarswaged between 1900 and 2003, we found that nearly one quarter of all belligerent sides were battlefield coalitions. After the end of the Cold War, over half of all belligerent sides that fought such battles were battlefield coalitions. Crucially, these groupings were effective: they won almost 54% of their engagements while militaries fighting battles without partners emerged victorious only 45% of the time.[ii] Broadly, fighting as part of a battlefield coalition appears to be a strategically wise decision. Not all battlefield coalitions are created equally, however, and not all offer the same promise of strategic success. In particular, when battlefield coalitions are comprised of forces who have not fought together before, they are considerably less likely to succeed in combat. Battlefield coalitions in which at least two partner forces had not fought a major battle together in the past 25 years won only 40% of the time; battlefield coalitions in which at least two partner forces had fought at least one major battle together in the past 25 years won nearly 60% of the time.[iii] In this article, we report the findings of our research into the performance of battlefield coalitions that have and have not fought before in more detail. We also argue that a primary reason why green battlefield coalitions are likely to struggle to fight together effectively rests in political and strategic differences that manifest in competitions over command authority, using the case of British and French combined operations in the opening days of World War I as an illustration. For strategists, our findings should be disquieting. For example, especially as the United States and its partners consider potential conflicts with powerful adversaries in the Indo-Pacific and elsewhere, the lure of battlefield coalitions will be difficult to resist. Because those battlefield coalitions are unlikely tohave experience fighting together in recent major battles, however, they may prove less useful—or at least more onerous—than anticipated. To maximize the likelihood that battlefield coalitions are a boon rather than an obstacle to the pursuit of strategic goals, planners must approach their formation and use with open eyes and a willingness to deviate from preferred plans and doctrinal approaches when necessary. Fighting Together, Fighting Alone Battlefield coalitions are formed by members of alliances and wartime coalitions, though they are distinct from both of those forms of collectives. Alliances are “written agreements, signed by official representatives of at least two independent states, that include promises to aid a partner in the event of military conflict, to remain neutral in the event of conflict, to refrain from military conflict with one another, or to consult/cooperate in the event of international crises that create potential for military conflict.”[iv] They are collectives that can comprise only states, and are formalized through written agreements making promises about future contingencies. Wartime coalitions, by contrast, are “group[s] of states that coordinate military activity during a war, regardless of the nature of the prewar relationship.”[v] They may comprise states, non-state actors, or both and are typically collectives of convenience formed to combat a current adversary. Crucially, in neither case are members obligated to deploy their forces to fight side-by-side with those fielded by partners. In some cases, allies and wartime coalition partners do take that next step and form collectives that cooperate at the operational and tactical levels of war; for instance, the many contributors to the United Nations Command fighting during the Korean War often did so. In other cases, however, allies and wartime coalition partners keep their forces separate; the Soviet forces fought no meaningful battles alongside American and British troops during World War II, and the Allies experience has been replicated in many other wars. The reasons why some alliances and wartime coalitions deepen their cooperation and form battlefield coalitions are myriad, complex, and idiosyncratic. There are a number of factors that incentivize cooperation at the operational and tactical level, including that doing so allows for greater resource pooling, aggregation of larger numbers of troops, enforced burden sharing, and the opportunity to exploit comparative advantages by assigning specialized troops to tasks in which they are likely to be most effective. However, there are also a number of factors that could disincentivize creation of battlefield coalitions, including disagreement among the partners about the precise political and strategic aims to be pursued; the necessity for all contributors to sacrifice some degree of operational authority and autonomy; difficulties in establishing functional command and control arrangements; insufficient levels of interoperability in personnel (skills, language capabilities), weapons platforms, communications equipment; and logistical challenges in bringing together the combined force and sustaining it for the duration of the engagement. How individual alliance and wartime coalition members weigh the costs and benefits of working more closely with their partners and forming battlefield coalitions is thus likely to be influenced by a wide range of political, strategic, operational, tactical, and other factors that defy easy categorization or assessment. The variable ways in which the different incentives and disincentives are weighed are reflected in the diversity of battlefield coalitions that fought together during the twentieth century: there is no Practice Makes Perfect for Battlefield Coalitions Rosella Cappella Zielinski and Ryan Grauer