Roy Cohn had played the role of pit bull for Trump until the Boss dropped him like a hot potato in his hour of greatest need when he was dying of AIDS—a fate I should have considered as I insinuated myself into Trump’s world. That night, all I kept thinking was that I didn’t want to disappoint Mr. Trump. That’s how I put it in my mind. Like so many now, in Congress and in the press, I was willing to say and do anything to please Trump.