“IT’S like a Rubik’s cube trying to figure this guy out,”Joe Biden said resignedly. “We have no freakin’ idea what he’s gonna do.”

“This guy” is of course Donald Trump, America's new Commander-in-Chief. The remark by Obama’s vice-president, reported by the New York Times earlier this week, referred to the US/Russia/Syria/ISIS/Iran issue but could easily reflect the wider world's baffled view of the unpredictable Trump.

Speculation is growing as to whether he will heed the wiser counsels of his Cabinet, some of whom have publicly contradicted him on Russia and the use of torture, or whether he rely more on insiders such as Steve Bannon, who was once described as “the most dangerous political operative in America” and will be his chief strategist.

Are there any constraints on Trump as president? “In the short term, I don’t think there are,” said Frank Cogliano, Professor of American History at the University of Edinburgh. “Because the Democrats are in the minority in both the Senate and House, he has a majority. Republican leaders like Paul Ryan have been developing a clear agenda that they now see an opportunity to enact.

“With midterm elections coming up in 2018, the real story until then will be an intra-party struggle for the Republicans. In the first instance, however, the Republicans will be in a strong position; Trump is likely to sign whatever they send him, so they will set out to repeal the Affordable Care Act and things like that.”

But two key stumbling-blocks may present themselves, Prof Cogliano added. “One is Trump’s unpopularity; he’s an historically unpopular President-elect, with approval ratings of between 37 per cent and 40 per cent. He has no popular mandate, despite what he claims. I don’t know how much support he will have in Congress if the public really turns against him. Congressmen and Senators are up for election at irregular intervals and they are attuned to public opinion and what is going on in their districts.

“The Republicans are committed to repealing Obamacare, though they haven’t come up with an alternative, and nor has Trump. If they enact what they’re currently thinking about doing, they will immediately deny healthcare to some 18 million people, all of whom are poor and many of whom supported Trump.

“If Trump’s constituency is angered by some of Congress’s actions, he’s not a lifelong Republican who is necessarily committed to their agenda, it will be interesting to see what happens."

He added: “Paradoxically, while his unpopularity may be his weakness with the Republicans in Congress, he is responsive to public opinion, at least the opinions of his supporters, and this may cause rifts between them. This is the second obstacle I foresee. He may try to bypass Congress and go straight to the people (as he defines them). I don't think the Democrats will be terribly relevant in all of this. This will be an intra-Republican struggle. I foresee that they are not going to get along very well for long. He is just so erratic.”

Prof Cogliano also believes that Trump has built up expectations to a very high level. "He can build the wall if he wants to, but that is not going to bring manufacturing jobs back to Ohio or Michigan. The world of work has changed ... He has heightened expectations in all kinds of ways and I think these people are going to be very, very disappointed."

Christopher Carman, Professor of Politics at the University of Glasgow, observes that collective cabinet responsibility, a familiar concept in the UK, does not exist in the US, and it is common for cabinet ministers to take positions art variance from those favoured by the president.

Further, more than is the case in this country, negotiations play an important and visible part in US politics and within government and between president and cabinet. "If this is the sort of thing that Trump likes, then he may enjoy being president, with all the negotiation that goes on," added Prof Carman. "One issue, however, is that he also tends to enjoy getting his own way, which he is not going to do as much. And that could be a problem."

Trump has selected an intimate coterie of advisers including Bannon, who once ran the far-right Breitbart News; his daughter, Ivanka and her husband Jared Kushner (despite ethical concerns surrounding the latter's appointment as senior adviser) and Kellyanne Conway, the first woman to run a Republican Presidential campaign.

“I think we can put Trump in the mould of someone like George W Bush, who famously said, ‘I just surround myself with good people’,” Prof Carman added. “Trump believes he does the same, and he listens to them. “There’s Bannon, and there’s the Conway question. And then there is his son-in-law and daughter - the influence that they will have is particularly interesting. That will probably be one for the history books if it shapes up as it’s looking, because it will probably be somewhat unprecedented in the way that the inter-workings of the West Wing come about, and evolve.

“It will be interesting to watch how that happens even over the first couple of months, to see how that evolves in the power structures.”

Trump may risk alienating much of his core support if he finds himself unable, for any one of a range of reasons, to fulfil his ambitious campaign pledges. Said Prof Carman: "That is highly likely, and potentially one of the biggest problems that we see, going forward, for American politics. Part of the reason we got Trump in the first place is because we can say the same thing about Obama, when he first ran in 2008.

"Obama talked about 'hope and change' but there was only so much change that he could affect, because of the institutional inertia of the way the US government is set up.

"The founding fathers’ Federalist Papers say that the government is specifically designed to be ‘small-c’ conservative, with minimal change from the status quo. Obama ran up against that, which led to a lot of disillusionment amongst left-wingers in the Democrats but also among centrists, and we ended up with a lot of disappointment and then with Trump.

"You can easily see how you're going to get quite a lot of disappointment [with him]. He has promised an awful lot literally within the first hours of his presidency but he has just said that Monday will be the first day of his presidency. On the day he is sworn in, he is not planning on doing all the things he said he would do within his first hours in office.

"People will overlook that, but as the narrative builds that, 'he's backing up what he said he would do about x, or y', there will begin to be questions, particularly among the people on the right.

"The Middle Americans who supported him, who hadn't voted in previous years because they were turned off by politics - well, they are going to see the same thing happening again [as happened with Obama], and there's certainly the idea that they will become more disaffected."