Were the walls at the new Museum of Modern Art put up by a contractor with ties to organized crime? That’s the allegation. “The firm, Interstate Drywall, has been affiliated with the family of the late John (Dapper Don) Gotti for years, according to several mob informants and public documents. Construction companies align themselves with mob families so they can get cheaper nonunion help on union jobs, and so they can intimidate other contractors from bidding against them for certain contracts, authorities say.”