(from July 2016 "Donald Trump's Shrewdest Investment Was In the Mafia"
. . .Among Cohns other clients were two of Americas most powerful mafia figures, who controlled key unions in New York City.
In 1978, Trump had hired mobbed-up construction firms to erect Trump Tower. Instead of building a high-rise skeleton of steel girders, Trump chose ready-mix concrete.
It has advantages such as avoiding costly fireproofing for steel girders.
Trump used it for other buildings, but in other ways it was a curious choice as the material had to be poured quickly, which made developers vulnerable to union work stoppages.
The truck drivers teamsters controlled the vehicles delivering the ready-mix. The construction unions controlled the construction site gate.
The concrete workers and carpenters controlled the pouring and making of forms. At the top, the mob controlled the unions.
Trump bought his Manhattan ready-mix from a company called S & A Concrete, secretly owned by mafia chieftains Anthony Fat Tony Salerno and Paul Castellano Cohns clients.
. . .
http://www.dailymail.co.uk/news/article-3716125/How-Trump-Mob-offer-not-refuse-killing-building-skyscraper-Donald-s-shrewdest-investment-MAFIA.html