MILWAUKEE — The Republican National Convention was supposed to mark the transformation of Donald Trump from presumptive GOP nominee to official standard-bearer of the party. But it turned out the real transformation took place 48 hours before the convention began, in a field in rural Pennsylvania, when Trump narrowly escaped an assassin's attempt to blow his head off. In a split second, Trump suffered a bloody wound to his right ear and came away with a different view of his life and the presidential race. The effect on Trump was so pronounced that it seems reasonable to see Trump in two ways — the Trump of before the assassination attempt and after. Trump had carefully planned the weekend before the convention began, on Monday, July 15, at Milwaukee's Fiserv Forum. He would hold a rally in Butler, Pennsylvania, north of Pittsburgh, on Saturday evening, then fly back to his club in Bedminster, New Jersey, for the night, and then fly to Milwaukee late Sunday afternoon to begin the work that would culminate in his acceptance speech on the final night of the convention. I had made plans to travel with Trump from New Jersey to Milwaukee and to do an interview setting the stage for the convention.  The world knows what happened in Butler. In the early hours of Sunday, after Trump had been examined and treated at Butler Memorial Hospital and then returned to...