It goes back to when Luciano was sent to Prison. This left Bonanno, Mangano, Magaddino, and Profaci has a powerful faction. Profaci went after Newark family, which Luchese had a deal with that family. Luchese and Bonanno didn't have a problem til the 1950s.

"I have this Nightmare. I'm on 5th avenue watching the St. Patrick's Day parade and I have a coronary and nine thousand cops march happily over my body." Chief Sidney Green