The Quest for the Liberal Peace: Toward a Measure of Interstate Cooperation

Building on the Kantian tripod of peace in liberal peace theory, we test theories of state intergovernmental organization (IGO) membership and levels of state cooperation. We examine the measurement for IGO joint membership and find that it is inadequate to measure the level of cooperation among states. Using network analysis, we propose a new dyadic measure for the level of bilateral cooperation. We argue that states craft intergovernmental agreements, purposely nested within bilateral treaty networks, to further consolidate and bolster such agreements’ efficacy. States both express and safeguard their power interests via negotiated treaties, and while costs of violating individual treaties are small, violating treaties nested within broader treaty networks are more costly as this significantly inhibits future cooperation with all states in a region. By creating networks of treaties, states bolster compliance, enhance the prospects for cooperative foreign policy behavior, and strengthen the conditions for peace. We argue that the strength of a bilateral treaty network is a better measure than joint IGO membership for liberal peace theory. We test this measure in the post-Soviet space, where many scholars expect dyadic conflict due to Russia’s regional economic and military dominance. Using militarized interstate disputes (MID’s) as the dependent variable in our model, we find that dyads that have stronger treaty networks are significantly less likely to experience a MID than dyads without a strong treaty network. We propose that the strength of treaty networks is a better measure for tapping cooperation among states, yielding analytical results more compatible with liberal peace theory.