“By the 1950s, the Irish were outearning other Americans.”
Largely because they took over the civil service of most big cities. My one time Irish mother in law once told me growing up in the depression era NYC the choices for jobs were cop, fireman, bartender, priest or gangster, and at one time she had as least one brother doing each. The gangster brother ran numbers for a while then became a fireman.
Well thanks for the history lesson, not that it aint all true.
https://www.bing.com/videos/search?q=kill+yhe+irishman&&view=detail&list=IsXWijD4BCd83Q&FORM=VRPPLA