Joe Biden on Wednesday became the 46th president of the United States with a call to unity, vowing to bridge deep divides and defeat domestic extremism two weeks after a mob attack tried to undo his election victory.

On a frigid but sunny day at the very Capitol building that was assaulted on January 6, Biden swore the oath of office moments after Kamala Harris, who became America’s first woman vice president, turning the page on Donald Trump’s tumultuous four years.

Speaking at the US Capitol just two weeks after it was stormed by an armed mob supporting Trump, Biden declared: “This is America’s day, this is democracy’s day. A day of history and hope.”

“Democracy is precious, democracy is fragile and at this hour, my friends, democracy has prevailed,” Biden said before a National Mall that was virtually empty due to the ultra-tight security and a raging Covid-19 pandemic that he vowed to confront immediately.

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“We must end this uncivil war that pits red against blue, rural versus urban, conservative versus liberal. We can do this if we open our souls instead of hardening our hearts, if we show a little tolerance and humility and we’re willing to stand in the other person’s shoes.”

“Together we shall write an American story of hope, not fear, of unity, not division, of light, not darkness. A story of decency and dignity, love and healings and goodness.”

But as the US confronts the deadly coronavirus and deep political divisions, he warned that to overcome its challenges will require “so much more than words, it will require the most elusive of all things in a democracy, unity.”

“Today on this January day, my whole soul is in this: bringing America together, uniting our people, uniting our nation, and I ask every American to join me in this cause,” the 46th US president said. “This is our historic moment of crisis and challenge and unity is the path forward. And we must meet this moment as the United States of America.”

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In the 21-minute speech Biden sketched out the challenges ahead.

“We need all our strength to… persevere through this dark winter. We’re entering what may be the toughest and deadliest period of the virus,” he said, calling on Americans to “finally face this pandemic as one nation.”

Biden spoke on the steps of the Capitol, which two weeks ago saw scenes of violence unprecedented in modern history as rioters egged on by Trump stormed the building, leaving five people dead and shaking US democracy to its core.

“Here we stand just days after a riotous mob thought they could … drive us from this sacred ground,” he said.

“It did not happen, it will never happen, not today, not tomorrow, not ever, not ever.”

The United States faces “a rise of political extremism, white supremacy, domestic terrorism, that we must confront, and we will defeat,” he said.

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The new president called for the country to “reject the culture in which facts themselves are manipulated.”