Democracies rarely go to war with one another.
The dyadic pattern is robust across datasets. The causal explanation is contested — institutional constraint, shared norms, and trade interdependence all fit the same correlation.
In practice
- Two elected governments with a live border dispute send it to arbitration, and each faces domestic critics who would have preferred the army.
- A shared court, a trade relationship and an electorate that pays for wars are three reasons the same two states did not fight, and the peace cannot say which did the work.
- Possible explanations
- Explanations divide between institutional constraint, where leaders answerable to voters cannot easily bear war costs, shared norms of settling disputes by bargaining, and structural factors such as trade and alliances that accompany democracy.
- In its favour
- The dyadic pattern is robust across datasets and codings, and is among the strongest regularities in international relations.
- Against it
- Democracies fight non-democracies at ordinary rates, so the peace is only between them, and critics argue the pattern reflects Cold War alliances or the coding of borderline cases rather than democracy itself.
- Standing
- The dyadic pattern is robust; the causal explanation is contested.
- Further reading
- Wikipedia
- Subject
- Law & Politics
- Essay
- Competing accounts of how power works