In The New Politics of Beijing–Hong Kong Relations, Sonny Shiu-Hing Lo looks at the diverging changes to the ideologies from both Beijing and Hong Kong, and the ideological conflicts as taken in the form of factional political struggles between 2012 and the present. This book examines the paternalistic authoritarianism that can be seen in Beijing’s policy toward Hong Kong since the promulgation of the national security law in late June 2020. Lo analyzes the ideological shift from liberal nationalism to conservative nationalism in mainland China, which has taken place since late 2012. The increasingly radical localism in Hong Kong after 2014 transformed Beijing–Hong Kong relations into a conflict-ridden situation characterized by factional struggles. While the imposition of the national security law into Hong Kong since late June 2020 has stabilized the city politically, Beijing’s policy toward Hong Kong is now guided by the principles of protecting its national security and maintaining economic pragmatism, with implications for Beijing’s relations with Taipei in the coming years.