To what extent has the COVID-19 outbreak, and the augmented use of health surveillance technology that has resulted from it, altered international conceptions of civil liberties, privacy, and democracy? This article examines how global patterns of liberal democracy have been and could be affected by the pandemic. In China, the outbreak has strengthened a pre-existing techno-authoritarian project aimed at prevention and control of threats to both public health and public order. Certain features of the international system such as China's major power status, its global economic role, and its leadership in international organizations suggest that China's model of illiberal pandemic response could diffuse worldwide. Other factors, however—such as the incomparability of China's political system to many other countries in the contemporary international system—suggest more limited diffusion potential. To date, the pandemic has largely augmented existing trends, meaning that autocracies have been likely to respond in ways that infringe upon citizen rights, and weak democracies have exhibited some risk of democratic erosion and pandemic-associated autocratization. In these cases, however, factors other than surveillance have been central to processes of democratic decay. Conversely, a large number of consolidated democracies have employed surveillance, but have managed to navigate the initial stages of crisis without significantly compromising democratic standards. In these cases, surveillance technology has been fenced in by democratic institutions and rule of law, and norms, institutions, and public opinion have worked together to facilitate pandemic responses that are (on balance) proportional, limited in time and scope, and subject to democratic oversight. This suggests that international relations may need to separate the pandemic's effects on democracy from its effects on liberalism, and that care must be taken to identify the precise mechanisms that link pandemic response to various components of liberal democracy.