Issue definition is a key feature of policy agendas theory. When the definition of immigration policy alternatives changes, the way presidents talk about immigration policy should also change. To explore this possibility, this chapter codes the relative tone of presidential rhetoric by immigration key word. The chapter begins by describing how the relative tone—positive or negative—of presidential rhetoric on immigration has varied over time. Explaining the tone of presidential rhetoric shows how it is a function primarily of the shift in the available immigration policy alternatives generated by anti-immigration sentiment that contributed to Proposition 187 in California. The aftermath of 9/11 reinforces this negative rhetoric increasing the difficulty faced by subsequent presidents who attempted to reform immigration policy in an overtly negative political environment.