Anti-Americanism, a general distrust of what the United States is and does, typically ebbs and flows in reaction to specific policy actions by the United States. However, in some countries, anti-Americanism peaks “out of sync” with the rest of the world and becomes an intense issue in the political debate even in the absence of any particularly egregious policy implemented by the US. Why? In that case, anti-Americanism is not so much organic as it is molded and manipulated by particular political groups to their advantage. This paper argues that this second kind of anti-Americanism can best be explained by the political functions that it serves and it analyzes the repertoire of functions performed by this “top-down” anti-Americanism in domestic political settings. After analyzing the conditions under which this political activation of anti-Americanism is most likely to occur, the paper explores in turn five political functions of anti-Americanism: creating and cementing an identity; rallying support around a leader by distracting from other issues; acting as a safety valve in authoritarian countries; scapegoating; and delegitimizing specific policies. The conclusion asks how the relative decline of American power and the “rise of the rest” will affect the use of anti-Americanism in domestic politics