The shock of the mob attack on the US Capitol had barely subsided when Joe Biden took the stage last week at the Queen, a theatre in his hometown of Wilmington, Delaware to lay out his $1.9tn relief plan for the world’s largest economy.

That evening, the president-elect made no mention of the January 6 insurrection that shook Washington, leaving five people dead and Donald Trump being swiftly impeached for the second time.

Instead, he spoke of Patricia Dowd, the 57-year-old Californian and first known person to die from coronavirus in the US, and the millions of Americans who had lost what he called the “dignity and respect” of employment during the pandemic.

“I promise you, we will not forget you. We understand what you’re going through. We will never ever give up and we will come back.” Mr Biden said, adding: “Come Wednesday, we begin a new chapter.”

At 78 years old, Mr Biden will be sworn in on January 20 as the 46th US president, without any of the cheering crowds and celebrations afforded to his predecessors. In addition to coronavirus restrictions, his inauguration will be protected by 25,000 members of the National Guard in the US capital to avoid another episode in domestic terror.

The bleak circumstances of Mr Biden’s first day in office have added sobriety to the moment, and pointed to the massive political challenge he is facing. Having won the White House by projecting a mix of competence, empathy and renewal to American voters after four years of Trumpism, he will have to translate all that into governing at a wrenching moment in US history.

Mr Biden is no stranger to tough starts, given that he became vice-president to Barack Obama at the height of the financial crisis. But the problems now confronting the country are arguably more severe and multi-faceted than they were in 2009, requiring even more sure-handed intervention and political skill. Many Democrats believe Mr Obama spent too much of his first year trying to win bipartisan support for his plans. They are well aware that to be successful, Mr Biden will need to show rapid concrete results.

“To be able to deliver tangibly in the near term in ways that all people in the country can see and feel and know is a critically important thing to do,” says Mara Rudman, vice-president for policy at the Center for American Progress, a left-leaning Washington think-tank, and a former official in the Clinton and Obama administrations.

Line chart of US GDP rebased (five quarters prior to inauguration = 100) showing Like Obama, Biden could struggle to engineer a strong recovery

“We have had a self-perpetuating cycle in a very negative direction,” she adds. “I think we have the opportunity to get to a self-perpetuating cycle in the positive direction.”

The president-elect’s transition team has already set out plans for a barrage of unilateral executive orders during the first 10 days to rejoin the Paris climate agreement and scrap the travel ban imposed on certain Muslim-majority countries, undoing some of Mr Trump’s most controversial policies. It has also made clear that Mr Biden wants to rebuild the US’s traditional alliances with other western nations that frayed during the past four years, while being more focused in confronting strategic rivals such as China and Russia.

But Mr Biden has tried to focus the attention of lawmakers rattled by the assault on the Capitol — and an anxious public — primarily on his prescriptions to resolve America’s health and economic crises, as he prepares to enter the White House. Nearly 400,000 Americans have died from Covid-19, and 9.8m fewer Americans are employed compared with last February.

At the Queen, the president-elect called on Congress to pass his sweeping relief plan, which includes a new round of direct payments to Americans, aid to cash-strapped states and cities, a top-up of federal jobless benefits, a beefed-up tax credit for children and more funding for vaccinations.

Securing its passage will be the first big test of Mr Biden’s presidency, and no easy task given his Democratic party’s exceedingly tight edge in both the House of Representatives and the Senate — and the toxic climate on Capitol Hill that may be exacerbated by Mr Trump’s second impeachment trial.

“There is going to be a compulsion to get something done and get something done quickly, but it is definitely under more difficult circumstances given the political environment, the non-cooperation of the Trump administration, the severity of the pandemic itself and the close margins in Congress,” says John Lawrence, former chief of staff to Nancy Pelosi, the House speaker. “It is going to be tough.”

Mr Biden’s urgency in pushing for a large-scale coronavirus relief package — less than a month after another fiscal stimulus package, worth $900bn, was agreed by Congress — reflects the knowledge that new presidents often have a short window to make use of their political capital.

Midterm elections, where the entire House of Representatives and one-third of the Senate will be up for grabs, will take place in less than two years, and Mr Biden’s Democratic predecessors, Mr Obama and Bill Clinton, each saw their agendas curbed and upended after their party lost control of the House in 2010 and 1994 respectively.

“What you really have in American politics is 18 months. Every administration gets 18 months of policymaking every four years,” says Glenn Hutchins, the founder of private equity group Silver Lake Partners and a former Clinton administration official. “So once you've begun the process of cleaning up the dystopian nightmare that Trump left behind, how do you then pivot to addressing the long term underlying issues of importance? What do you choose to focus on? That's going to be the main thing.”

As the new administration grapples with priorities, there has been plenty of debate among Democrats in recent years about how to make progressive policies more easy to understand and more popular with the American public — which Mr Biden’s team has tried to absorb both in crafting its policies and its communication.

Bar chart of US unemployment rate at start of presidencies (%) showing Incoming presidents have often had to tackle a jobs crises

“The ambitions are at the New Deal scale, they are about kitchen table, lunch-pail, meat-and-potatoes economic concerns that people have,” says Kenneth Baer, a former senior Obama administration official and co-founder of Crosscut Strategies, a consultancy in Washington. “And [the message is] we are going to help you.”

In addition to the $1.9tn stimulus package laid out by Mr Biden last week, he is expected to move quickly in February to present a second recovery plan involving trillions of dollars in additional spending centred on infrastructure and green energy. To be at least partially funded by higher taxes on corporations and the wealthy, it is another hugely ambitious legislative endeavour.

Mr Biden’s hopes of a successful first-term agenda did receive a big boost on January 5, the eve of the assault on the US Capitol, when Raphael Warnock and Jon Ossoff, two Democrats, won a pair of run-off Senate races in Georgia.

The twin victories handed control of the upper chamber to Mr Biden’s party — albeit with a 50:50 split and tiebreaking votes cast by Kamala Harris, the incoming vice-president. Given that the Democrats now get to decide which proposals can be put up for a vote in the Senate, the Georgia results ensure that, at the very least, Mr Biden’s goals will not be blocked by Mitch McConnell, the Republican senate leader, at every turn.

Mr Biden’s ability to enact crucial parts of his agenda will initially depend on keeping the Democratic party fully united behind any legislation, marrying the needs of conservative lawmakers with those of the progressive bloc, with very little room for defection.

In the Senate, the biggest trouble for Mr Biden may come from moderate lawmakers such as Joe Manchin, the West Virginia senator, and Kyrsten Sinema, the Arizona senator, who may be wary of the high price tags and tax increases involved.

In the House, where Ms Pelosi’s majority is very slim, the biggest headaches are more likely to come from the left. Progressive lawmakers such as Alexandria Ocasio-Cortez of New York have been joined by like-minded members such as Jamaal Bowman of New York and Cori Bush of Missouri, who defeated longtime Democratic incumbents in primaries, supported by grassroots groups such as Justice Democrats and the Sunrise Movement.

Even though Mr Biden has wholeheartedly embraced the shift in the economic orthodoxy towards greater tolerance for deficits, especially in times of crisis, they are arguing that he is still being too cautious, and that the $1,400 direct payments included in the stimulus plan are insufficient.

But Mr Biden and his team have not given up hope that they can also get some Republican support for their plans, which would broaden the political appeal of the president’s first steps and chime with his calls to unite the country in the post-Trump era.

This proposition is controversial among many Democrats not just because of fears that the legislation will be excessively watered down, but because there is limited confidence that enough Republicans are genuinely interested in bargaining.

“A solid majority of Republicans still believe that Biden is not president, that the election was fraudulent and that Trump was viciously stripped of a landslide victory,” says Mark Rom, a professor of government at Georgetown University. “It's hard to govern when the opposition does not believe that you should be there in the first place. That's awfully hard for Biden to overcome.”

Many Democrats also say the party learned some haunting lessons from 2009, when Mr Obama waited for months in vain to secure bipartisan support for his healthcare overhaul, and only received very limited support from across the aisle for his $787bn stimulus bill.

“There are people on the incoming team who were there in the first term of Obama and their patience for a Republican to join is going to be time-limited,” says Mr Baer.

Still, some Capitol Hill veterans say that if anyone can draw in a few Republicans it is Mr Biden, who spent more than 35 years in Congress. “He knows the Senate and he knows a lot of the key players, he would probably have some problems with some of the newer faces, some of the harsher elements,” says Mr Lawrence. “But he knows how that process works in a way that Barack Obama did not, in a way that George Bush did not and in a way that Donald Trump certainly did not.”

So far, a few high-profile Republicans, such as Pat Toomey of Pennsylvania in the Senate, and Kevin Brady of Texas in the House, have attacked Mr Biden’s relief plan, but others have been quiet, suggesting they may be open to negotiations.

A number of Republicans with an eye on running for president in 2024 have also been flirting with a more populist economic approach. Marco Rubio, the Florida senator, said last week that Mr Biden should push for $2,000 cash payments to all Americans.

One of the biggest questions on Capitol Hill, which Mr Biden’s team has not weighed in on, is whether the Senate should scrap a rule requiring a 60-vote supermajority threshold to pass most legislation, in order to bypass working with Republicans. That rule can be waived for certain tax-and-spending bills, meaning most of the stimulus measures could still pass with a simple majority, but many progressive groups are clamouring for the “filibuster” to be ended completely.

“No compromises, and no excuses,” says Evan Weber, political director of the Sunrise group, a climate crisis advocacy group, about how he hopes the Biden administration will approach its legislative agenda.

Lara Brown, director of the Graduate School of Political Management at the George Washington University, says either way Mr Biden would need to win round progressives and moderates alike if he is to get anything done.

“At the end of the day, for Biden to succeed, he is going to need to pass bipartisan compromise bills that are not just about a progressive wishlist,” she says. “He is going to have to be able to say . . . we don’t have the votes to pass every progressive idealised policy. But we do have the votes to handle the priorities.”

Although Mr Biden is entering the White House as a president in times of crisis, there is an optimistic scenario in which after a first difficult year, both the pandemic and the recession it caused have receded in the rear-view mirror. The incoming president and his team are not counting on that coming naturally, but by virtue of aggressive policies and plenty of action on Capitol Hill that will require some compromises.

“Biden is a liberal Democrat but also a moderate and not a partisan”, said Mr Hutchins.