Projecting Credibility: Alliance Commitments, Security Partnerships, and International Crisis Responses
How does the ability to quickly project large-scale military force—such as with transport aircraft and naval aircraft carriers—affect states’ alliances and security partnerships? I argue that states with greater capacity to project force will deploy fewer troops to allies for deterrent purposes. Instead, more capable states can demonstrate their commitment to allies through public words and actions—such as statements by political leaders—supported by the ability to quickly respond to crises. However, greater force projection capacity also creates opportunities for new foreign policy pursuits, which increases states’ deployments to non-allied security partners. Using data on troop deployments and a new index for force projection capacity from 1985 to 2018, I show that as force projection capacity increases, states deploy fewer troops, but to more countries. Furthermore, I show that increased force projection capacity increases the likelihood of militarized disputes with other states, but it also works to effectively deter aggression against allies. Together, these results help explain states’ behavior with respect to alliances, limited security partnerships, and crises in the changing international security environment.