It was Barack Obama's last hurrah – and it set the stage for Hillary Clinton's greatest huzzah.
In this season's most poignant departure and arrival – a Janus moment in July, looking back and forward – Mr. Obama basked in the warm, almost rapturous, applause of the Democrats he returned to executive branch power eight years ago even as he sought to stoke the passions of a dangerously divided party for the fight ahead against businessman Donald Trump.
It was, in a way, the last leg of a long-distance medley relay, with the first black president handing the Democratic baton to the first female presidential nominee from a major party in a race for the shiniest medal in American politics. That hand-off occurred with an unexpected but poignant onstage hug, the departing President embracing the striving candidate.
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In relays, it is often the slowest competitor who hands off to the swiftest athlete near the conclusion of the race for the stretch run to the finish line. But Mr. Obama's performance in Philadelphia on Wednesday night suggested that in this year's Democratic relay team the roles were reversed.
Speaking exactly a dozen years after he first won national attention as a young, virtually unknown Senate candidate speaking before the 2004 Democratic convention in Boston, Mr. Obama, a week away from turning 55, offered a strenuous defence of his two terms and of the role Ms. Clinton played in his eight-year administration. He chided Mr. Trump as a "homegrown demagogue," criticized the Republicans' Cleveland convention for presenting a "deeply pessimistic vision," and saluted Ms. Clinton's "unbelievable work ethic," adding, "She never, ever quits."
Ms. Clinton's address on Thursday evening is ardently anticipated, but also quietly dreaded. She lacks the ease and comfort Mr. Obama displayed in his convention moment on Wednesday and has a far steeper challenge: the difficulty if not the impossibility of a familiar figure winning a fresh start for the general election marathon.
Hillary Clinton has had more public moments than any woman in U.S. history, and more than almost any American alive, rivalled only by her husband, the two presidents Bush, and Jimmy Carter: There was her introduction as the independent, feminist wife of the shiny new Democratic star, Bill Clinton, in 1991; her role in the failed comprehensive health-care overhaul of 1993; her prominence in the Whitewater scandal and then as the mortified wife of a presidential adulterer and impeached chief executive; her two elections to the Senate; her unsuccessful presidential candidacy in 2008; her years as secretary of state; and now her pioneering role as Democratic presidential nominee.
For that reason, Mr. Obama argued, "there has never been a man or woman – not Bill, not me – more qualified than Hillary Clinton to serve as president of the United States." Moments later, he addressed Mr. Clinton, "I hope you don't mind, Bill, but I was just telling the truth."
Earlier this week, Mr. Clinton shared some affecting anecdotes of their courtship and their early years together as spouses and parents. That went a fair distance in grafting a human touch onto her image as a manic activist and achiever. The week has been full of testimonials, many of them outside prime time, to her sense of commitment and even to her sense of humour.
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And yet the world's most well-known woman is still one of the least-known figures on the global stage.
That, besides extending a burly olive branch to the heartbroken legions who supported Senator Bernie Sanders of Vermont only to see their effort fall short, is her principal task on Thursday: showing commitment and character, humility and humanity.
It is a hard order, its only analogue in recent years the effort, in 1968, to put on display a "New Nixon." That was, from the start, a mirage, apparent to nearly everyone, including the man who had been Dwight D. Eisenhower's vice-president and then the unsuccessful Republican nominee in 1960, when senator John F. Kennedy of Massachusetts prevailed. Mr. Nixon triumphed largely because the Democrats, following the assassination of senator Robert F. Kennedy of New York and the riots in the streets outside their Chicago convention, were hopelessly divided, and menaced by a sense of hopelessness themselves.
This year, it has been the Republicans who have gladly grabbed tricks from the bag of the American politician known as Tricky Dick; in his acceptance speech barely a week ago, Mr. Trump spoke openly of "law and order," an important element of the Nixon appeal in 1968, a year also pockmarked by racial tension.
The Democrats, and the Clinton inner circle especially, see the advantage inherent in a "New Clinton," in part because the old one supported tough crime and welfare measures now blamed for racial disparities; a warm approach to Wall Street, now blamed as the villain in the wealth gap that is such an important element of Democratic rhetoric; and global trade agreements, especially the North American free trade agreement, or NAFTA, now blamed for hollowing out the manufacturing Midwest from Toledo to Buffalo and beyond.
And yet fashioning a New Clinton may be beyond the abilities of even the most gifted political strategists and publicists. In his convention address earlier this week, Mr. Clinton stressed the continuity, from Wellesley College to the State Department, of his wife's commitments and undertakings. Besides, she is so well known that a New Clinton might seem to be the artifice that it would be: a cynical prank, manipulative and ultimately false … and futile.
So Ms. Clinton must do what Thurgood Marshall, the storied U.S. Supreme Court justice who died in 1993, said he wanted as his epitaph: doing "the best I could with what I had." In truth, Ms. Clinton has a years-long record of achievement. On Thursday evening, more than ever, she needs to do the best she can with what she has – to prove Mr. Obama right when he said in his Wednesday-night address that "she is fit and she is ready to be the next commander-in-chief."
David Shribman