Donald Trump is, at heart, a showman. He rose to national fame thanks to star turns on reality TV in which he played the tough-talking boss to a group of aspirants hoping to become as successful as he has been in business. His great gift is the ability to draw attention — and then use that attention for his own, usually commercial, purposes. Trump may have outdone himself on Friday morning. He and his campaign touted a "major" announcement at his newly-opened hotel in Washington, D.C. at 10 a.m. The word was that Trump would walk away from his past...