This dissertation casts a wide net in order to explain the recent emergence and proliferation of the contemporary anti-immigration movement in the United States. Anti-immigration activism is an understudied but not entirely overlooked phenomenon. Yet, we know incredibly little about an important set of macro- and micro- questions related to contemporary anti-immigration activism. This dissertation addresses big-picture mobilization questions, such as: What large-scale, historical preconditions set the stage for the emergence and proliferation of contemporary anti-immigration activism in the United States? And how--and through what general processes--has pro-migrant countermobilization influenced the anti-immigration movement and, perhaps, unintentionally spurred its growth? Finally, I address micro-level questions focused around the mechanics of micromobilization: How and why do individuals support anti-immigration activism? How and why do individuals become motivated to engage in anti-immigration activity? and How and why do individuals ultimately participate in anti-immigration-related activism? In sum, both big-picture and small-scale questions anchor this dissertation. By answering these I not only shed light on this specific case but also make a number of more general contributions to social movement literature.

This study has for its goal to examine whether a new racist prejudice against Mexican illegal immigrants was driving the activities of the minutemen movement operating along the U.S.- Mexico border whose stated goal was to prevent illegal immigrants from entering the country. This work assumes that the old blatant racism is no longer acceptable within society but was replaced by a conspicuously color-blind rhetoric, typical of the minutemen movement, that might harbor a new racist prejudice. New racism does not put forth a race defined biologically but understands the white and non-white races conceptually. It thus contributes to the maintenance of the white-black dichotomy within society and more importantly to the discrimination and exclusion of the non-white races. In order to disclose a possible racist prejudice, this study conducts a Critical Discourse Analysis of the minutemen's discourse. Results of this analysis show that especially the focus on the notion of law and order, so typical of the discourse, is hugely misleading and that under this seemingly color-blind reasoning, there is, indeed, a hidden expression of the new racist prejudice.