 In contrast, the various social models were explicitly formulated to support a disability identity that could serve as the basis for claims of respect and recognition. The inclusion of people with a vast array of different impairments in United States and other national civil rights laws, and the creation of the United Nations convention on the rights of persons with disabilities, have helped to forge a shared disability identity. The emergence of disability studies as a recognized field of academic inquiry has also contributed. The minority group model promotes a trans-impairment identity by treating people with disabilities as a “discrete and insular minority” making claims on a generally stigmatizing able-bodied majority. Though the minority group model has proven extremely useful in passing anti-discrimination laws, it may do so at the expense of emphasizing the differences between people with disabilities and people without them, rather than highlighting the many ways in which identity need not be tied to the presence or absence of an impairment. The human variation model tempers this emphasis, and resists essentialism about disability identity, by treating the group itself as socially constructed. It sees the category of “the disabled” as resting on an artificial dichotomy imposed on a continuum of variation. The conceptualization of disability as just one source of difference, and as a difference in kind more than degree, can undercut a sense of disability as the basis for a unique and exclusive identity.