In the brisk autumn of 1992, a couple of months before his inauguration, Bill Clinton’s motorcade pulled up to the Century City skyscraper in Los Angeles where Ronald Reagan had his post-presidential office. Clinton was spending a few days in town with friends and had sent word to Reagan, now eighty-one years old, that he wanted to stop by and chat. A meeting was quickly arranged. The two men were thirty-four years apart in age…