The liberal peace: Interdependence, democracy, and international conflict, 1950-85

The classical liberals believed that democracy and free trade would reduce the incidence of war. Here we conduct new tests of the 'democratic peace', incorporating into the analyses of Maoz & Russett (1993) a measure of economic interdependence based on the economic importance of bilateral trade. This allows us to conduct a simultaneous evaluation of the effects of regime type and interdependence on the likelihood that a pair of states will become involved in a militarized interstate dispute. We control in all our analyses for a number of potentially confounding influences: growth rates in per capita income, alliances, geographic contiguity, and relative power. Our logistic regression analyses of politically relevant dyads (1950-85) indicate that the benefits of the liberals' economic program have not been sufficiently appreciated. Trade is a powerful influence for peace, especially among the war-prone, contiguous pairs of states. Moreover, Kant (1991 [1795]) was right: International conflict is less likely when external economic relations are important, executives are constrained, and societies are governed by non-violent norms of conflict resolution.