The open display of emotion was new, but the theme of safeguarding his legacy was not. Two months earlier, on July 5, in Charlotte, N.C., Obama delivered his first stump speech for Hillary Clinton. He described his presidency as a leg in a relay race. Hillary Clinton had tried hard to pass affordable health care during Bill Clinton’s administration, but she failed — and the relay baton fell to the ground. When Obama entered the White House, he picked it up. Now, his leg of the race was coming to an end. “I’m ready to pass the baton,” he said. “And I know that Hillary Clinton is going to take it.”

But he was less certain than he was letting on. Hillary Clinton was up in the polls, to be sure, but she was vulnerable. Three weeks earlier, on June 15, a cyberattacker fashioning himself as Guccifer 2.0 had published a cache of emails stolen from the Democratic National Committee (DNC). They proved, as supporters of Vermont senator Bernie Sanders had long alleged, that the DNC had conspired with the Clinton campaign to undermine their candidate. Sanders was still withholding his endorsement of Clinton for president, even though her nomination as the Democratic candidate was now a foregone conclusion. At the very moment when Clinton had expected the Democratic party to unite behind her, its deepest chasm seemed to be growing wider. In contrast to Clinton, Obama held some sway over the Sanders insurgents. He came to Charlotte to urge them to support Clinton against their shared enemy, the presumptive Republican nominee for president, Donald Trump.