Donald Trump was inducted into the World Wrestling Entertainment Hall of Fame in 2013. He'd been involved with professional wrestling for over a quarter century. At first his interest was on the business side, because so many of the events were held at his hotels. But then he began appearing in the ring as an actual character. His greatest moment came in 2007 with the pay-per-view series called "Battle of the Billionaires," when he verbally went up against the WWE's chief executive, Vince McMahon. The feud started when Trump interrupted McMahon on Fan Appreciation Night and upstaged him by raining...