Cyber nationalism in China is on the rise, with complex implications for authoritarian rule. On one hand, nationalistic netizens in general demonstrate pro-regime inclinations and side with the state in online debates. On the other hand, popular nationalism often directly contests the state’s claims to nationalist legitimacy and runs the risk of collective mobilization. What happens when a nationalistic fever meets the authoritarian state? This chapter explores the party-state’s efforts to rein in cyber nationalism and netizens’ reactions by examining the “Diba Expedition”—an online event in which Chinese nationalist netizens flooded the Facebook page of president-elect Tsai Ing-wen in early 2016 to defend the “One China” principle. This patriotic event was full of irony, given that Facebook is banned in China and the party-state made diligent efforts to censor relevant mobilizing threads. Such conflict between spontaneous patriotism and state repression calls into question both the legitimacy of the regime and the nature of Chinese nationalism. However, content analysis of posts in the Diba Expedition finds that many nationalists seem to have found a way to reconcile authoritarian rule with their love of the nation.