Queer theory was originally associated with the radical gay politics of ActUp, Outrage, and other groups which embraced queer as an identity label that pointed to a separatist, non-assimilationist politics. As it has come to be understood in cultural theory, however, queer theory challenges either/or, essentialist notions of homosexuality and heterosexuality within the mainstream discourse (the binary sexual regime, to use historian George Chauncey's phrase), and instead posits an understanding of sexuality that emphasizes shifting boundaries, ambivalences, and cultural constructions that change depending on historical and cultural context. "To queer" is to render normal sexuality as strange and unsettled, to challenge heterosexuality as a naturalized social-sexual norm and promote the notion of non-straightness, challenging the hegemony of "straight" ideology. This emphasis on non-straightness lends queer theory its assimilationist, anti-essentialist cast, for when one considers the realms of fantasy, the unconscious, repression, and denial, much that is ostensibly considered heterosexual easily falls within the realm of queer. The influential work of Judith Butler, particularly Gender Trouble, with its now broadly overused concept of performative sexuality and gender identity, seeks to reject stable categories altogether. While thoroughly disruptive of mainstream truth regimes of sexuality, it also challenges standard gay, lesbian, bisexual, transsexual, and transgender politics. In Butler's conception, these terms are rendered meaningless when stripped of the institutional means that support them. Alexander Doty's notion of queer reception, in Making Things Perfectly Queer, is another way in which standard categories are challenged. Doty separates reception from identity and stresses the way a spectator may derive queer pleasure by deviating from standard categories in viewing film and television. Thus straight-identified women spectators might experience queer pleasure at the sexual tension generated between Geena Davis and Susan Sarandon in Thelma and Louise; straight-identified men might enjoy the exaggerated homoeroticism of Stallone's Rambo. 
It is in the realm of male homoeroticism that we may see the potentially reactionary and/or misogynist implications of queer texts and queer reception: non-straightness does not necessarily embrace liberation. Perhaps the most prominent examples of this are the straight male-oriented genres such as gangster films, the Western, action films, and buddy films, which position male homoeroticism as a means to create and defend a world of men and buttress hard masculinity against the softening effects of domesticity and heterosexual commitment (as opposed to conquest and flight) set forth in the standard Hollywood narrative structure of the Oedipal trajectory. Thus a central political weakness of queer theory: if non-straightness includes so many, what happens to the sexual minorities and marginalized deviants who seek explicit protections within well-defined political communities that can organize internally and create coalitions with other well-defined groups?
 Adapted in part from Brooker, A Concise Glossary of Cultural Theory
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