In international relations today, influence is as essential as military and economic might. Consequently, leaders promote favorable images of the state in order to attract allies and win support for their policies. Jing Sun, an expert on international relations and a former journalist, refers to such soft power campaigns as "charm offensives."

Sun focuses on the competition between China and Japan for the allegiance of South Korea, Taiwan, and other states in the region. He finds that, instead of adopting a one-size-fits-all approach, the Chinese and the Japanese deploy customized...