To Protect and to Serve

The consequences of alliance formation for other foreign policies of a state, including defense spending and the initiation of militarized disputes, are examined using a theory of foreign policy that is based on several assumptions. First, states pursue two goods-change (defending those aspects of the status quo that one likes) and maintenance (altering those aspects of the status quo that one dislikes)-through their foreign policies. Second, states select a portfolio of policies designed to produce the most preferred mix of the two goods. Third, all foreign policy behavior, including alliance involvement, requires resources. Fourth, states are rational in their allocation of resources. Together, these imply that an observed alliance must have been the most efficient mechanism available for acquiring the most desired and achievable foreign policy portfolio and have implications for the observation of foreign policy substitutability. The empirical implications of this implication are tested, and results support the model: states are more active in their foreign policies after adding to their alliance portfolios-they increase their rate of conflict initiation, the capital intensiveness of their military establishments, and their defense spending.