The Fighting Irish

In the 1920s, the Ku Klux Klan effectively controlled Indiana, apart from the bit around South Bend, home of Notre Dame. Campaigning against Italian immigration, a Klan leader went to speak at Notre Dame, where he explained that he had nothing against Irish Catholics, "it's those Roman Catholics".

Throughout the English-speaking world, Catholics of Irish descent have been consistent opponents of later waves of immigration, and have therefore made common cause with their previous enemies among the WASPs, the Scots-Irish, or both.

A reason, perhaps, to send as many as possible of the Poles, Africans, Latin Americans and other recent arrivals to Northern Ireland?

Or perhaps not...