After a 2020 presidential campaign dominated by President Donald Trump’s words and actions, Biden on Thursday rose to the level of a true adversary as he accepted the Democratic Party’s nomination for the November election.

Accused by the Republican Trump of hiding in his basement throughout the coronavirus pandemic, Biden turned his opponent’s narrative to his advantage on the final night of the Democratic National Convention, delivering an austere address in a quiet room that some commentators, both left and right, likened to a speech from the Oval Office, not a convention floor.

Biden, 77 and nearing his 50th year in politics, cast himself as the wizened healer of a troubled and divided nation, pushing back at doubters within his party who whispered that he was wrong for the moment. He invoked President Franklin Delano Roosevelt, who presided over a nation beset by economic hardship and then war.

A day after former President Barack Obama warned that Trump posed a threat to democracy, Biden, who was Obama’s vice president, offered Americans an alternative, pledging to be “an ally of the light, not the darkness” if elected.

Biden’s remarks were in sync with a compressed, virtual Democratic convention that focused less on policy priorities and more on casting as wide a net as possible to assemble a coalition to win.

The online format allowed the party to feature an array of progressive Democrats and disenchanted Republicans over four nights of programming, while papering over the fissures from a divisive primary that tested how far left it was ready to move.

The two most beloved figures in the party, Barack and his wife Michelle Obama, savaged Trump in their respective convention speeches. That left Biden and his running mate, U.S. Senator Kamala Harris, the room to outline a more ambitious vision beyond merely defeating the president.

Biden  denied the chance to accept the nomination before a roaring crowd due to the pandemic, delivered the most consequential speech of his nearly half a century in public life from a silent ballroom inside the Chase Center, near his home in Wilmington, Delaware, on the last night of the virtual Democratic national convention.

“Here and now I give you my word, if you entrust me with the presidency, I will draw on the best of us, not the worst,” Biden said. “I will be an ally of the light, not the darkness.”

“United we can, and will, overcome this season of darkness in America. We will choose hope over fear, facts over fiction, fairness over privilege.”

Biden’s speech, at turns somber and hopeful, delivered a forceful closing argument on the final night of the most unusual presidential nominating convention in modern memory. This year’s quadrennial affair showcased the racial – and ideological – diversity of the Democrats coalition, which stretches from a Democratic socialist to a former Republican governor, and is increasingly led by women, young people and people of color.

That was evident the evening before when Biden’s running mate, the California senator Kamala Harris, accepted her place in history, as the first black woman and first Asian American to appear on a major party’s presidential ticket.

Biden presented November’s election as a “battle for the soul of this nation”, echoing the words he used when he launched his third presidential bid last year. He said the country faces four historic crises: the coronavirus pandemic, the economic fallout, racial injustice and climate change.

He vowed to be an “American president” who would “work hard for those who didn’t support me,” drawing a stark contrast with the president who attacks and threatens his critics.

“This is not a partisan moment,” he said. “This must be an American moment.”

Without mentioning his rival by name, Biden accused Donald Trump of having “failed in his most basic duty to the nation” by mishandling the pandemic. If elected, he pledged to implement a national strategy to tackle it, including a national mandate on wearing a mask as “a patriotic duty”.

“The tragedy of where we are today is it didn’t have to be this bad,” he said of the crisis, which has killed more than 170,000 Americans and infected more than 5 million, far more than any other country in the world.

“He failed to protect us,” Biden said. “He failed to protect America. And, my fellow Americans, that is unforgivable.”

Outside the convention center, under a crescent moon, fireworks lit the sky in a moment of celebration. After delivering the speech, Biden and Harris emerged with their spouses to watch the display.

In a parking lot beyond the stage where they stood, supporters from Biden’s hometown sat on their car hoods, others in the beds of their trucks, waving American flags and blaring car horns in a show of support for a man described earlier this week as Delaware’s “favorite son”. Biden and Harris raised their clasped hands high, and the crowd honked their horns louder.

Across the four-day convention, Americans were introduced anew to the former vice-president. His family, friends, colleagues and former political rivals – from the president he served for eight years to a New York City security guard who briefly rode on an elevator with him – testified to his character. Electing Biden, they argued, would amount to a stark repudiation of Trumpism.