articles on the underclass in the Atlantic Monthly during the late 1980s and early 1990s. His 1986 writings on "The Origins of the Underclass" argue that the underclass was created by two migrations, the great migration of Southern blacks to the North and West during the early to mid twentieth century and the exodus of middle class blacks out of the ghetto during the 1970s through the early 90s. In 1991 Lemann also published an article titled "The Other Underclass", which details Puerto Ricans, and particularly Puerto Ricans residing in South Bronx, as members of the urban underclass in the US. Critiques of the concept Following the popularization of the underclass concept in both academic and journalistic writings, some academics began to overtly criticize underclass terminology. Those in opposition to the underclass concept generally argue that, on the one hand, "underclass" is a homogenizing term that simplifies a heterogeneous group, and on the other hand, the term is derogatory and demonizes the urban poor. Derogatory and demonizing language Many who refute the underclass concept suggest that the underclass term has been transformed into a codeword to refer to poor inner-city blacks. For example, Hilary Silver highlights a moment when David Duke, former Grand Wizard of the KKK, campaigned for Louisiana Governor by complaining about the "welfare underclass". The underclass concept has been politicized, with those from the political left arguing that joblessness and insufficient welfare provided are causes of underclass conditions while the political right employ the underclass term to refer to welfare dependency and moral decline. Many sociologists suggest that this latter rhetoric – the right-wing perspective – became dominant in mainstream accounts of the underclass during the later decades of the twentieth-century. Herbert Gans is one of the most vocal critics of the underclass concept. Gans suggests that American journalists, inspired partly by academic writings on the "culture of poverty", reframed underclass from a structural term (in other words, defining the underclass in reference to conditions of social/economic/political structure) to a behavioral term (in other words, defining the underclass in reference to rational choice and/or in reference to a subculture of poverty). Gans suggests that the word "underclass" has become synonymous with impoverished blacks that behave in criminal, deviant, or "just non-middle-class ways". Loïc Wacquant deploys a relatively similar critique by arguing that underclass has become a blanket term that frames urban blacks as behaviorally and culturally deviant.