Public Support for Peacekeeping in Lebanon and Somalia: Assessing the Casualties Hypothesis

Among the many lessons that the U.S. military and political leaders drew from the Vietnam War, one was that the military could not deploy effectively or for very long without public support. Another was that public support for military deployments had declined quite predictably (one is tempted to say invariantly) in response to the accumulation of casualties.1 In principle, it is nothing but wise counsel that rulers ignore the deadly consequences of military deployments only at their peril. Recently, however, a new lesson has been taught that resembles but should be distinguished from these. Based on accumulating experience with peacekeeping operations, it holds that the public will not support peacekeeping deployments if they lead to the loss of American lives. This lesson is a source of worry and concern for those who believe armed forces are an essential instrument of national security policy, and it is taken very seriously. Since the barracks bombing that killed 241 Marines in Beirut in 1983, national security doctrine has required that there be some reasonable assurance of public support before combat forces are committed abroad.2 The worry is that public support for missions, which seems sufficient, will quickly evaporate when faced with American casualties. It is often noted, for instance, that public support for