This article discusses problems with Kurt Lewin's notion of self-hatred among Jews (Lewin, 1941/1948), and illustrates the ways in which the concept is used in identity politics. It argues that the way the notion of self-hatred is often used makes it problematic as a psychological concept because it requires that we accept particular definitions of group identities and particular political positions as central to those identities. Often, however, such issues are disputed by group members. Examination of the literature illustrates that it is rarely a straightforward decision whether those behaviours or attitudes identified as manifestations of self-hatred are best explained in this way. The function of the self-hatred concept in current debate over Israeli policy is described as an example of how arguments over identity are part of political conflict. In the case of current Middle Eastern politics, the concept of self-hatred is used by rightwing Zionists to label those who criticize policies of the current Israeli government as disloyal and pathological.