The likelihood of local allies free-riding: Testing economic theories of alliances in US counterinsurgency interventions

In counterinsurgency interventions, free-riding by small, local allies is persistent. Yet, the literature on free-riding by small allies is largely limited to conventional multilateral partnerships, such as the North Atlantic Treaty Organization, neglecting other types of asymmetric alliances. Using new data containing 144 US requests to local allies in Vietnam, Iraq and Afghanistan, this article tests the logic of economic theories of alliances in counterinsurgency interventions. I find even when small allies are explicitly asked to contribute to alliance-wide security goods, they are likely to free-ride almost half the time (45%), and the likelihood of free-riding is dependent on whether local allies can be excluded by larger allies. This conclusion upholds the logic of economic models, since shared defense goods that exclude local allies fail to meet the criteria of public goods.