DNC 2016: Barack Obama, in swan-song to his party, extols Hillary Clinton for experience and steel

To deep-throated applause and chants of ‘Yes we can!’, Barack Obama stepped into the giant sports arena hosting Democrats in Philadelphia to declare that, “there has never been a man or a woman more qualified than Hillary Clinton to serve as President of the United States”.

If there was voltage in the air when he started, it became a full electric storm as, at the moment he seemed to be departing, Ms Clinton herself walked onto the stage in a surprise appearance to give him a hug of appreciation. They left the stage together to roars from thrilled delegates, her arm around his waist.

In his address, Mr Obama depicted Ms Clinton as a candidate seasoned to serve in the Oval Office and a person who “never, ever quits”. And most importantly, he said, she has, after serving as Secretary of State, seen the job of being president first hand and what it involves.

“Until you’ve sat at that desk, you don’t know what it’s like to manage a global crisis or send young people to war,” he said. “Hillary’s been in the room; she’s been part of those decisions.”

It was a speech that was part paean to the newly minted nominee, part nostalgia for his nearly eight years on Pennsylvania Avenue, and part vigorous rejection of the dark portrait of America he said was being offered by her Republican foe, Donald Trump.

“This year, in this election, I’m asking you to join me - to reject cynicism, reject fear, to summon what’s best in us; to elect Hillary Clinton as the next President of the United States, and show the world we still believe in the promise of this great nation,” Mr Obama declared.

“No matter how daunting the odds; no matter how much people try to knock her down, she never, ever quits. That’s the Hillary I know. That’s the Hillary I’ve come to admire. And that’s why I can say with confidence there has never been a man or a woman more qualified than Hillary Clinton - not me, not Bill, not anybody - to serve as President of the United States.”

It was also a speech laced with reminders of the Mr Obama of 2008 when he deployed his oratorical skills to dispatch Ms Clinton on the way to the White House. “Democracy isn’t a spectator sport,” he intoned. “America isn’t about 'yes he will’. It’s about ‘yes we can’. And we’re going to carry Hillary to victory this fall, because that’s what the moment demands.”

Her Republican rival is “offering slogans, and he’s offering fear,” Mr Obama said. “He’s betting that if he scares enough people, he might score just enough votes to win this election.”

“That is another bet that Donald Trump will lose. Because he’s selling the American people short. We are not a fragile or frightful people. Our power doesn’t come from some self-declared savior promising that he alone can restore order. We don’t look to be ruled.”

“Anyone who threatens our values,” as a land, he said, “whether fascists or communists or jihadists or homegrown demagogues, will always fail in the end.”

“America is already great. America is already strong. And I promise you, our strength, our greatness, does not depend on Donald Trump…it doesn’t depend on any one person. And that, in the end, may be the biggest difference in this election - the meaning of our democracy.”

If the tone of speakers before him had verged on mockery, Mr Obama’s attacks on Mr Trump were sober in tone. He admonished delegates not to boo the first time he uttered his name.

“Donald’s not really a plans guy,” he sad. “Not really a facts guy, either. He calls himself a business guy, which is true, but I have to say, I know plenty of businessmen and women who’ve achieved success without leaving a trail of lawsuits, and unpaid workers, and people feeling like they got cheated.” His message seemed most urgent on Mr Trump and foreign policy.

“He cozies up to Putin, praises Saddam Hussein, and tells the NATO allies that stood by our side after 9/11 that they have to pay up if they want our protection. Well, America’s promises do not come with a price tag. We meet our commitments, we bear or burden.”

And he clearly took personally the contention of Mr Trump that America is a country in perilous, chronic decline.

“What we heard in Cleveland last week wasn’t particularly Republican - and it sure wasn’t conservative. What we heard was a deeply pessimistic vision of a country where we turn against each other, and turn away from the rest of the world. There were no serious solutions to pressing problems - just the fanning of resentment, and blame, and anger, and hate."

“That is not the America I know,” he said “The America I know is full of courage, and optimism, and ingenuity,” he said. “The America I know is decent and generous.”

If Mr Obama had told aides he did not want the speech to be about him, someone couldn’t resist. Before he came to the stage a gauzy paean panned through those moments of greatest challenge for him in the Oval Office, from financial meltdown to the killing of Osama bin Laden, and greatest achievements including the passage of healthcare reform and of gay marriage.

Mr Obama came surely aware that he will soon be leaving office having woven a presidency that may largely be well remembered by history but is replete with holes. There are specific goals that will go unmet - from closing Guantanamo Bay to bringing about new strictures on gun ownership - to more holistic ones like his promise to deliver an American less divided politically.

Even in endorsing Ms Clinton, he was turning a blind eye to her newly contorted position on opposing ratification of the Trans-Pacific Partnership, TPP, a free-trade treaty of 12 nations, that Mr Obama has seen as one of the most significant planks of his legacy as president.

Most critical to Mr Obama's legacy, however, is convincing Americans to elect the candidate who will not destroy it, but give it a new four-year or eight-year fresh lease. Just as she has not hesitated to tie herself to him on the trail as his approval ratings have risen above 50 per cent again, so he now has everything invested in her taking the keys to the Oval Office from him. "She will finish the job," he said at point in his speech. He was talking about destroying Isis, he might as well as been talking about all of his agenda.

Mr Obama was the star turn in a night of Democrat A-listers, however, all assembled with a common, urgent task: the painting of Mr Trump as a dangerous demagogue who would bring disaster to the country. Or, as Vice President Joe Biden put it in a speech brimming with grave passion, a “man who seeks to sow division in America for his own gain and disorder around the world, a man who confuses bluster or strength”. He ended: “We simply cannot let that happen as Americans.”

“He shows up saying he cares about the middle class,” Mr Biden, who once toyed with competing with Ms Clinton for the nomination but demurred. “Give me a break! That's a bunch of malarkey. He has no clue about what makes America great. Actually he has no clue, period.” That remark sent the hall into a spontaneous chorus of “Not a clue! Not a clue!”

Also in the arena was Michael Bloomberg, the former Mayor of New York who assumed that office as a Republican but who said that he could not stay silent faced with the threat of a Trump White House. “Trump says he wants to run the nation like he is running his business?” Mr Bloomberg, a self-made billionaire, asked. “God help us. I am a New Yorker and I know a con when I see one…Truth be told the richest thing about Donald Trump is his hypocrisy.”

The task was also taken up by Senator Tim Kaine, who began by accepting the nomination of running mate before riffing on Mr Trump's penchant for saying "believe me" with every campaign promise he makes. "He never tells you how he is going to do any of the things he says he is going to do, he just says, 'Believe me'," he intoned, peppering his remarks with Spanish. "The question is, do you believe him?" The entire auditorium faithfully boomed, "no!". "Folks you can't blelieve one word that comes out of Donald Trump's mouth, not one word."