Every new president begins a fresh chapter in American history. And when Donald Trump is inaugurated in a freezing Washington DC on Monday, he will be hoping to usher in a new era for this country.

The ceremony in the rotunda of the US Capitol, moved indoors for the first time in decades due to the bitter cold, will also mark the moment he starts being judged on action and not promises.

And he has promised seismic change as well as action on day one. At a raucous rally in the city on Sunday, Trump said he would sign a flurry of executive orders within moments of being inaugurated, covering issues ranging from immigration and deportations to the environment and transgender rights.

"You're going to have a lot of fun watching television tomorrow," he told the crowd here.

But even if his presidency begins with a serious bang, there are still questions about what Trump's second act will look like.

Will we feel the tectonic plates of power shift beneath our feet as he re-enters the White House? Can he deliver his pledged sweeping reforms? Will it be as apocalyptic as his opponents suggest?

Listening to some of his detractors, you would be forgiven for thinking the skies will darken and the birds will flee Washington as soon as he takes the oath of office.

Many worry he will try to rule as an autocrat and undermine American democracy. His predecessor, Joe Biden, pointedly used his final Oval Office address to warn of a dangerous oligarchy of unaccountable billionaires forming around Trump that threatens the basic rights and freedoms of Americans.

But no one can deny Trump, 78, has a clear mandate after his decisive election victory in November. He won the popular vote and the electoral college. He won a clean sweep of swing states. His agenda has the green light from voters.

This time around, Trump is determined his agenda will be enacted. He has a far more experienced and deeply loyal team behind him to make sure that happens.

He also plans - presumably with the help of Elon Musk's "Department of Government Efficiency" - to swiftly fire huge numbers of civil servants and officials.

Trump still believes there is a "deep state" within the US government that will try to frustrate his agenda. So we can expect a far more drastic clear-out of federal employees than would normally come with a change of administration, and a far more politicised government machine behind him.

Many of his plans, like major tax cuts for big corporations and the very wealthy, will need legislation passed by Congress.

But that will not be a problem, as he has control of the Republican Party and its majority in both chambers. Senators and Representatives are unlikely to defy him in significant numbers. And he has Musk on hand to wield his social media platform and vast wealth to pressure any rebels back into line.

Is there anything that could prevent Trump from rounding up and deporting millions of undocumented migrants or using the justice system to target political opponents he sees as his enemies?

There are logistical and financial hurdles no doubt, particularly when it comes to mass deportations, but Democratic opposition alone is unlikely to be enough to stop this. The party, after all, is still reeling from its resounding election defeat.

There is internal strife as members carry out a prolonged post-mortem over that result. And the resistance movement that mobilised before Trump's first term, prompting days of nationwide protests after his inauguration that brought more than a million people onto the streets, appears less energised this time.

After his 2020 election defeat, Trump was kicked off social media platforms following the Capitol riot and his baseless claims of voter fraud. These companies are already treating him differently this time around, as he prepares to be inaugurated inside the rotunda where his supporters roamed on 6 January 2021.

Prominently seated in the VIP section to watch will be a collection of the richest men in the world. Musk, Jeff Bezos and Mark Zuckerberg will all be there. So will the CEOs of Google, Apple and TikTok. It is the living embodiment of the ultra-wealthy "tech-industrial complex" that Biden warned about in his farewell address.

These men have already moved to warm relations with Trump. Zuckerberg's Meta is abandoning fact-checking on Facebook and Instagram, Bezos prevented the Washington Post (which he owns) from endorsing Kamala Harris. And all of them have donated millions to Trump's inaugural fund.

Whether it is in Congress or the corporate world, Trump is taking office this time around with a warm welcome from America's powerbrokers.

There's little doubt that his mass of executive orders on day one will feature some eye-catching actions designed to titillate his base. Like issuing presidential pardons for many, if not all, of the people convicted over the Capitol riot. His supporters will be thrilled to see the people they regard as political hostages freed from jail.

Trump will need a steady stream of populist moves like this. Because there is a risk some of his plans are at odds with what a section of his supporters voted for.

Many wanted lower prices after years of high inflation. But most economists suggest tariffs on imported goods will probably push prices up further.

Mass deportations could lead to a labour shortage in construction - complicating his pledge to build more houses - and in the agricultural sector, which could further increase the price of food. And it is billionaires, not the working class, who look set to benefit from the biggest tax cuts.

Eye-catching proposals, like promising to rename the Gulf of Mexico as the Gulf of America, may well excite many of those who put him in office. But it remains to be seen how many Americans will feel the benefit of his headline policies.

Trump, however, is the ultimate political showman. His ability to entertain is part of his power and appeal. But his second term agenda goes deeper than pure showmanship and would be transformative if enacted.

His White House comeback will be dramatic and eventful, with consequences felt around the world. It may change America in fundamental and lasting ways.