"Next stop Washington D.C., Union station". It is 9:30 on 20 January 2021; I have travelled from New York to the capital to cover the inauguration of Joe Biden's presidency.

The moment I arrive at the station, I am met by a surreal atmosphere. A few dozen people step off the same Amtrak train as me — a train that had crossed a good stretch of the US East Coast. Military personnel and police mark the route to the station's waiting hall, enormous but deserted, surrounded by shops and restaurants with their shutters down.

Stepping out of Union Station, the dome of Capitol Hill — the seat of the US Congress, the building that on 6 January was stormed by supporters of now-former president Donald Trump — is immediately visible. It is partly for this reason that Washington is on lockdown today. The historic centre, from the Lincoln Memorial to the White House, is inaccessible, sealed off by barriers and barbed wire. 25,000 soldiers control the security perimeter and manage access at the few checkpoints available, allowing only authorised vehicles through.

What strikes me most, however, is not the rifles carried by the National Guard or the military vehicles parked in the very heart of the "greatest democracy in the world" (something I was, after all, prepared for having seen the images in every newspaper). What leaves me incredulous is instead the sombre atmosphere hanging over the streets of the capital — a city still wounded by the violence of a few weeks earlier and by four years that have torn the country apart. Along the wide central thoroughfares there is not a soul. Shops are shuttered, their windows covered with wooden boards as a precaution against further violence, and many restaurants — already forced to operate on takeaway or delivery only because of the pandemic — have chosen to remain closed.

I had already visited Washington four years ago, in 2016. I remembered it as an institutional, rigorous city, but one still full of life and proud of its many monuments, constantly thronged with tourists. This year, by contrast, it is emptied out. When I step into a Starbucks near the White House, I am greeted by a large group of police officers on a coffee break. "We've had a lot of people in this morning," the barista tells me, though she nods when I point out that the place is one of the few still open in the area.

Looking at images from recent presidential inaugurations — from Obama to Trump — the contrast with the current situation is stark. Where once millions of citizens crossed the country to reach Washington, this year only a few hundred people are able to attend the ceremony, scaled back not only to safeguard security but also because of the Covid-19 pandemic, which continues to record thousands of new cases every day. Only journalists are wandering around the city. Ordinary citizens dare not venture out.

The Biden and Harris swearing-in

Joe Biden becomes the 46th president of the United States at exactly 12:00, although he completed the oath some ten minutes ahead of schedule. He took the oath with his hand on the Bible on the west front of Congress, before a handful of witnesses. Before him, it was the turn of Kamala Harris, who has already made history as the first female vice president.

While Lady Gaga and Jennifer Lopez take to the stage in turn, the city remains wrapped in an unimaginable silence. Only in front of Congress do I find any movement, largely generated by a large contingent of reporters and a small anti-abortion and anti-feminist demonstration, whose main spokesman shouts into his megaphone: "I'm fine with Kamala Harris being at the White House, but only if she stays in the kitchen." A reminder that, even if progress has been made, there is still a long road ahead.

"Kamala is our first female vice president. I am related to Susan B. Anthony, who fought her whole life to secure women's right to vote," Debby Anthony tells me instead — one of the few demonstrators I meet, holding two placards to celebrate the change of administration. "I'm here for her, for Kamala, who today finally sees the fruits of a lifetime's work." "Will she be the one to take the oath as president, in four years' time?" I ask her. "She would be fantastic in that role."

Once the ceremony is over, the area in front of Capitol Hill begins to empty as Biden and Harris, with their respective families, make their way to the White House. I also see a few buses full of law enforcement officers pulling away — perhaps breathing a sigh of relief that the clashes they had feared never materialised.

The challenges facing the new administration

Donald and Melania Trump left the White House on the morning of 20 January, bound for Florida, without much ceremony: after all, for the past two weeks the political legacy of the former president has been crumbling a little more each day, following the terrible attack on Congress incited and supported by him.

For Biden, there is no time to waste. Already in the first hours of his term the new president intends to reverse a number of decisions taken by the previous administration — including, for example, bringing the United States back into the Paris Climate Agreement and introducing a federal mask mandate.

His $1.9 trillion plan (approximately €1,550 billion) also aims to restore the American economy, brought to its knees by what Trump, even in his last speech as president, did not miss the opportunity to call "the Chinese virus," and to finally tackle the pandemic by listening to science rather than the winds of opinion polls.

Another significant reform will be on immigration: Biden has promised to simplify the asylum procedures for "dreamers" – people who arrived in the United States as minors but who, even after years, have still not obtained official documents – and to thereby ease the path to American citizenship for 11 million people.

The opening towards more permissive migration policies is seen as a beacon of hope for many migrants, so much so that even before his official inauguration a caravan of 9,000 people set off from Honduras to reach the American border. The group was, however, stopped by Guatemalan law enforcement.

What now?

During his four years in the White House, Donald Trump showed no regard for the tacit agreements that had shaped the course of American politics for decades. The tycoon leaves Washington with very few allies and deep in debt, carrying with him the weight of 400,000 deaths and the unenviable distinction of being the only president to have been impeached twice.

Beyond politics, Trump leaves behind a divided and hostile society, mired in internal conflicts that go well beyond party lines: minority rights, racial inequalities, and the role of law enforcement have been turned into weapons to exploit not so much to win new votes, as to strengthen the army of Trumpism's most fervent supporters, many of whom gathered in Washington on 6 January.

It is no coincidence that Joe Biden's inaugural address hinged on a single theme: "To overcome these challenges, restore the soul and secure the future of America, requires so much more than words. It requires the most elusive of all things in a democracy: unity. Unity."

National unity – that is perhaps what was missing from the streets of Washington on 20 January 2021.