You are among friends on FreeRepublic. Feel free to use the term "Shanty Irish" that we all know and love to refer to the "less successful" from the Emerald Isle.
Democrat Philadlephia Councilman Rick Mariano used a real vicious slur to refer to the "Shanty Irish", calling the denizens of Kensington (Philadelphia's 31st Ward, amazingly depsite its extreme poverty and decay the most Republican inner city slum in the nation - roughly 40% of the voters are Republican) as "trailer-park Irish trash."
Check out the book "White Town USA," which describes life in Kensington and Fishtown in the 1960s, when blacks, Puerto Ricans and even an American Indian family were attacked by the locals when they attempted to move in.