Butler follows a Foucaultian approach in questioning the internal coherence of gender. She questions the stability of the distinction between masculine and feminine and argues that these distinctions are always produced by power relations rather than being in any way innate. Butler, however, goes beyond this, and criticizes Foucault for his unwillingness to follow the logic of anti-essentialism to sexuality as well. The assertion that sexual difference is socially constructed strains belief. It is true that there are some people whose biological sex is ambiguous, but this is not the case for the vast majority of people.
Sexual difference has extensive biological implications, going way beyond reproductive systems.
It may have implications for mental functioning as well. But as long as the vast majority of humans are born either male or female it is unclear why dissolving sexual identity would be a good thing, or on what basis one might expect any large number of people to be interested in such a project. However this is not a serious danger. What seems more likely is that feminist theory, pursued in this direction, will lose its relevance to women's movements or other movements for progressive social change, and also lose credibility outside of relatively narrow circles. The concept of alienation, of estrangement from one's environment, from others, and from oneself, is incompatible with poststructuralism because it assumes a human nature that in some way exists prior to the way in which humanness is constructed within a particular social order.