 The social constructionist approach can sometimes lend itself to the idea that societies can bring races into existence simply by the formal use of the category in, for example, official legal documents. This view in turn can give rise to the belief that races can be deconstructed by reversing this process. The historical approach to racial identities offers a different, though not entirely distinct approach. Racial groups exist within history and are formed by historical forces, but these include not only top-down machinations of states but also the collective agency of those so designated. It is not just state policies that construct identities, but social movements, both progressive and reactionary. Through historical periods and collective group action, the meanings of race can change as well as their political valence (Glasgow et al. 2019; Omi and Winant 1986; Alcoff 2015).