US President-Elect Joe Biden speaks at Major Joseph R "Beau" Biden III National Guard /Reserve Center in New Castle Airport on Jan 19, 2021, in New Castle, Delaware, before departing for Washington, DC, the United States. (PHOTO / BLOOMBERG)

Joe Biden will be sworn in as the 46th US president on Wednesday in an inaugural ceremony set to unfold under heavy security after weeks of tumult and unrest stoked by Donald Trump.

The most glaring omission from the events will be Trump himself. He is the first president in modern history to skip the inauguration of his successor

Biden will take the oath at noon on the steps of the US Capitol, making a plea for national unity from the very spot that was overrun by Trump supporters just two weeks ago in a deadly attempt to derail the transfer of power.

The event - themed “America United” - will be nearly devoid of the customary pomp that surrounds a presidential inauguration as the recent violence and ongoing coronavirus pandemic preclude any large gatherings. Instead of throngs of supporters crowding the National Mall, Biden will see thousands of National Guard soldiers and barricades - a grim reminder of the deep national rift he wants to mend.

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In address after he’s sworn in, Biden will call on Americans to bring the country together during an unprecedented crisis, according to advisers to the president-elect who asked not to be identified ahead of the speech. He’ll ask every citizen to meet what the advisers called an extraordinary challenge facing the nation, in a speech they said would be built around the theme of unity.

The address will be 20 to 30 minutes long, according to a person familiar with the matter who also asked not to be identified.

The most glaring omission from the events will be Trump himself. He is the first president in modern history to skip the inauguration of his successor. Trump never conceded that he lost the election and since inciting the Jan 6 riot at the Capitol, has done little to quell tensions across the country as threats of violence against elected leaders, federal buildings and state capitals have surfaced.

Trump plans to fly to Florida Wednesday morning before the ceremony.

“It has been the most tense, contentious transition since the post-Civil War era,” said Brandon Rottinghaus, a politics professor at the University of Houston. “The expectation of the political system is that there be a smooth transition and minimal friction. We’ve obviously seen that shattered.”

After the pared-down celebration, a logjam on Capitol Hill awaits Biden and incoming Vice President Kamala Harris. They face fights to confirm Cabinet members and haggling over a new coronavirus aid package that Biden wants to pass within weeks. Looming, though, is the pending Senate trial for Trump’s impeachment - a charged event that promises to complicate any efforts for bipartisan cooperation as well as consume lawmakers’ time and energy.

Members of the National Guard gather at a security checkpoint near the US Capitol, ahead of the 59th inaugural ceremony for President-elect Joe Biden and Vice President-elect Kamala Harris in Washington, DC on Jan 19, 2021. (GRAEME SLOAN / BLOOMBERG)

Biden’s bigger task is more fundamental: Steering the US away from the brink of rupture and back toward an era of bipartisanship that appears long-lost. His success depends in part on whether the Republican Party sticks with Trump or adopts a more conciliatory stance after he leaves. Some Republican figures - including outgoing Vice President Mike Pence and former President George W Bush - will attend Biden’s swearing-in despite Trump’s absence.

The inauguration will take place with much of Washington in lockdown, including restrictions on public transit and scores of checkpoints and barricades surrounding the city’s core.

Biden will begin the day ensconced in the heart of the security perimeter at Blair House, across the street from the White House and typically the residence of visiting foreign dignitaries.

He’ll attend a prayer service at St Matthew’s Cathedral with congressional leaders of both parties, a nod by the nation’s second Catholic president to its first, John F Kennedy, whose funeral was held at the cathedral after his 1963 assassination.

At the swearing-in ceremony, Father Leo O’Donovan, a Jesuit Catholic priest who is a friend of Biden, will offer the invocation. Lady Gaga will sing the national anthem while Jennifer Lopez and Garth Brooks will also perform. “This is not a political statement, this is a statement of unity,” Brooks told reporters in a conference call arranged by Biden’s transition.

Andrea Hall, President of the International Association of Firefighters Local 3920 and the first African-American woman promoted to the rank of fire captain in her department’s history, will recite the Pledge of Allegiance.

Yet, thanks to Trump, many of the inaugural traditions that are key to reinforcing US democratic norms will be absent, said Barbara Perry, director of presidential studies at the University of Virginia’s Miller Center.

Trump “already destroyed that by - almost two weeks ago now - fomenting the insurrection against the Capitol,” Perry said. Biden’s administration must now “seize back our constitutional system, seize back our democratic republic, seize back as many of the traditions as they can.”

Vice President-elect Kamala Harris speaks during a COVID-19 memorial, with lights placed around the Lincoln Memorial Reflecting Pool, Jan 19, 2021, in Washington. (ALEX BRANDON / AP)

Noon swearing-in

Biden and Harris will be sworn in at noon. Harris, who will become both the first woman and person of color to hold the office, will be sworn in by Supreme Court Justice Sonia Sotomayor, the first Latina on the high court.

Biden plans to immediately sign at least 15 executive actions, including orders to rejoin the Paris Agreement on climate, extend a pause on student loan payments and rescind Trump’s travel restrictions on Muslim-majority nations

After he’s sworn in, Biden will deliver his inaugural address, laying out his vision for defeating the pandemic and unifying the nation. The two leaders will then take part in a “pass in review” with members of the military.

Biden and Harris will later attend a wreath-laying ceremony at Arlington National Cemetery in nearby Virginia, accompanied by Bush as well as former presidents Barack Obama and Bill Clinton. Trump is scheduled to be in Florida by then. Biden’s inauguration team added the ceremony in a bid to underscore his message of unity.

Biden will then make a ceremonial trip escorted by members of the military from 15th Street to the White House - a considerably shorter procession than usual. Presidents typically move from the Capitol to the White House. Instead, Biden’s arrival will be followed by a “Virtual Parade Across America.” The inauguration is also live-streaming portions of the day specifically for children.

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American flags decorate the "Field of Flags" on the grounds of the National Mall near the US Capitol at night in Washington, DC, the United States, Jan 19, 2021. (VICTOR BLUE / BLOOMBERG)

The inaugural committee will also stage a prime time special, hosted by Tom Hanks, and featuring speeches from Biden and Harris as well as appearances by artists including Bruce Springsteen, John Legend, Katy Perry and Demi Lovato.

Biden plans to immediately sign at least 15 executive actions Wednesday afternoon, including orders to rejoin the Paris Agreement on climate, extend a pause on student loan payments and rescind Trump’s travel restrictions on Muslim-majority nations.

But a major unknown hangs over the day: Trump, who plans to hold a farewell event for himself at Joint Base Andrews on Wednesday before departing for Florida. He released a farewell address by video on Tuesday, and it’s unclear what he’ll say before leaving Washington.