Safe Across the Border: The Continued Significance of the Democratic Peace When Controlling for Stable Borders

We investigate the research findings reported in Gibler (2007) that suggest the democratic peace is in fact a spurious artifact of stable borders. If corroborated, this set of findings would mark an important reorientation for the field. However, we show that the research design used in Gibler (2007) suffers from several problems, including omitting the lower order terms of interaction variables and inappropriately assuming cross-dyad independence of artificially created dyadic democracy scores. Our replication and extension shows that even when controlling for stable border variables, democracy continues to be a consistently useful predictor of international conflict. Further, the stable border variables themselves prove to be less consistent predictors of both peace and democracy as compared to previous research. These results suggest that both territorial issues and democracy can coexist as explanations for interstate bellicosity.