This chapter traces Irish America’s place in the lineage of today’s white nationalist movement, to help explain the remarkable prominence of Irish American Catholics in contemporary America’s racist, alt-right movement, as well as the far-right wing of the Republican Party. Irish American Catholics are prominent also among Democratic Party’s progressive left-wing, too. However, given the history of vilification of Irish Catholic immigrants by hard-right groups such as the Know-Nothings in the nineteenth century and the Ku Klux Klan (KKK) in the twentieth, the sheer number of Irish American extreme right-wingers has puzzled and merits deeper investigation. The chapter investigates how the Catholic Irish transmuted from a redundant, expendable people in the British colonial state in Ireland, to valuable American citizens, and ultimately white American nationals, through an analysis of the work of the most accomplished and prolific of all Irish American writers, Eugene O’Neill and James T. Farrell.