The leadup has already caused waves, and it seems he has designs on the Panama Canal, Greenland and Canada.
Today is so different from Mr Trump’s first 2017 inauguration and from the ugly Capitol riots and election denial of January four years ago.
This time, Mr Trump comes in triumph as if he were emperor. He defeated the Democratic candidate, the Republicans have majorities in the Senate and House of Representatives, and the Supreme Court has a decisive conservative majority.
Meanwhile, the tech titans of the United States, among the most powerful men in the world, are invited to the inauguration, in a sense paying homage.
Elon Musk, of X etcetera, the world’s richest man, is his sidekick. Musk also revels in the unpredictable and in upsetting the traditional establishment.
Mark Zuckerberg, the Meta power, has already ingratiated himself, dropping Facebook’s "fact-checking" and liberal employment policies. Jeff Bezos, Amazon founder and the Washington Post owner, has adapted to the new milieu.
TikTok CEO Shou Zi Chew was also to be prominent at the inauguration. Trump looks as though he is going to save TikTok, despite it being he who first tried to force its sale in 2020.
The heads of the likes of Google, OpenAI, Apple, Uber and Microsoft have all paid millions to fund inauguration events, although big companies often do this.
The Trump tilt is palpable in many directions. The left is watching in horror. Where will it all lead?
Naturally, there are fears for the environment and the climate.
Inflation, under control, shows signs of returning because of likely even higher deficits, tariffs and the tipping of the applecart of world trade.
Will the United States lurch a significant way towards authoritarianism?
What happens to Ukraine? Will might as right play a greater part and further threaten the rules-based order? Will minnows like New Zealand have even less significance or say?
Is president Joe Biden correct when he said, "Americans are being buried under an avalanche of misinformation and disinformation enabling the abuse of power"?
Attacking what he called "the tech-industrial complex", he warned, "an oligarchy is taking shape in America of extreme, wealth, power and influence that literally threatens our entire democracy, our basic rights and freedoms and a fair shot for everyone to get ahead."
Maybe, however, Trump’s unorthodox approaches can jolt stalemates. Maybe, his bravado, bluster and bluntness have advantages. What will be the "Trump effect" he brags about?
Perhaps, the self-righteous certainties of many progressives needed a jar. The support for Trump shows they had lost touch with the aspirations, beliefs and attitudes of a majority of Americans.
As one ODT letter writer put it: "The challenge for world leaders and mainstream media will be to stay calm and decipher nonsense from reality and not to overreact to his propensity for mixed messages and bombastic rhetoric."
Optimism is difficult after his previous Covid and economic performance and his bizarre cabinet choices.
This time he is better prepared and better able to steer the nation. Despite the United States’ relatively strong economy, his inaugural address was likely to again proclaim American weakness. In 2017 it was about America’s "carnage" and America first.
From what is now a position of strength, Trump has said he would talk about unity, strength, and fairness. How much can we believe?
Even his ardent followers do not expect what might euphemistically be called consistency. There are the illegals to deport, the ceasefire between Israel and Hamas to boast about and Capitol rioters to pardon. Of course, he can again claim he never lost in 2021. Executive decisions are expected to pour forth from today.
The United States is resilient, and much power is decentralised through the 50 states and institutions. As he becomes President Trump again, that resilience will be tested.
