Why does the public support a war? An extensive literature has demonstrated that both exposure to information about war, and ingroup-outgroup dynamics can influence popular war support. Yet, while much of the work has focused on democracies, less known are sources of war support in authoritarian contexts where information is highly censored and manipulated. This study examines authoritarian public opinion in China during the Russian invasion of Ukraine. We argue that state propaganda bolsters public support for Russia by blaming the war on China’s rivalrous outgroup: the United States. Using a two-wave longitudinal survey data in a sample of 500 Chinese respondents, we present cross-lagged panel estimations of the impact of propaganda on public opinion. We find evidence that exposure to state media exerted a cross-lagged effect on the belief that the U.S is the real culprit of the war in Ukraine, which in turn predicted their backing for Russia. A competing hypothesis that propaganda strengthens war support by downplaying civilian casualties, is tested but not borne out by our data. In sum, this study extends our knowledge about popular war support beyond democratic contexts, shedding new light on authoritarian public opinion.
