The dearth of jointly dyadic democratic interventions

Abstract

The Democratic Peace Proposition, which states that no two democracies have ever gone to war with each other, has been questioned by scholars who claim that such pacific behavior among free states does not apply to lower forms of conflict. In particular, Kegley and Hermann contend that democracies intervene in the affairs of other liberal states via overt military acts or covert machinations. In many cases, they argue that dyadic democratic interventions (DDIs) occur more frequently than would be expected given the number of jointly democratic dyads in the international system. I examine their research design and suggest changes to their concepts of states, interventions, and regime type, as well as their sample size and definition of dyads in the international system. I implement these changes and retest such arguments on a sample of interventions from 1945 to 1991. I find 11 cases where a democracy intervenes against another democracy, but these cases are rare in comparison to interventions conducted by democratic and/or autocratic states in undemocratic states, or by autocratic states against democratic states. Furthermore, these DDIs are less likely to occur than the presence of democracy in the international system would suggest.