Democracy is positively valued. This positive evaluation extends to a democracy's actions, even if it is to wage war. The authors investigated whether the perceived legitimacy of military interventions depends on the political structure (democratic vs. nondemocratic) of the countries involved and on the aggressor country's popular support for the government's aggressive policy. Participants learned that an alleged country planned to attack another. The political structure of both countries was manipulated in the two experiments. The support of the aggressor's population toward military intervention was measured in Experiment 1 and manipulated in Experiment 2. Both experiments confirmed that military intervention was perceived as being less illegitimate when the population supported their democratic government's policy to attack a nondemocratic country.