Democracies rarely engage in conflicts with one another, though they are not averse to fighting autocracies. We exploit the existence in many countries of executive term limits to show that electoral accountability is the key reason behind this “democratic peace” phenomenon. We construct a new dataset of term limits for a sample of 177 countries over the 1816–2001 period, and combine this information with a large dataset of interstate conflicts. Our empirical analysis shows that, although democracies are significantly less likely to fight each other, democracies with leaders who face binding term limits are as conflict prone as autocracies. The study of electoral calendars confirms the importance of re-election incentives: in democracies with two-term limits, conflicts are less likely to occur during the executive’s first mandate than in the last one. Our findings support the Kantian idea that elections act as a discipline device, deterring leaders from engaging in costly conflicts.