A presidency under Donald Trump could see protests, would bring uncertainty and the UK should not expect any favours under his leadership, experts have warned.
Three academics have spoken speculatively about what we could possibly expect if the Republican candidate clinches victory in the US election - and the outlook is not good.
Civil unrest, legal challenges and the potential of a "cozy up" to Russian president Vladimir Putin are all concerns voiced by professors Scott Lucas, Iwan Morgan and Mike Cullinane.
"My feeling is that Trump is going to treat the presidency as the equivalent of a CEO position - and it isn't that," Professor Morgan, who lectures US Studies at University College London, told the Press Association.
"The presidency has to be held by someone who understands the necessity for persuasion, it isn't a place for command."
He said everything he has seen about Mr Trump makes him "worry he doesn't quite understand" that being president is a "system of checks and balances between co-equal branches of government".
Professor Lucas, a US citizen who teaches American Studies at the University of Birmingham, said with Mr Trump as president of the free world "god knows what you get".
"He is completely unpredictable, he is incoherent - I have not heard him express a coherent thought on foreign policy in his campaign," he said.
"He talks in slogans, but that doesn't actually make a policy."
Professor Lucas added: "I think with Trump we are into the realm of the unknown, and the unknown is never good for stability - in foreign policy and international relations to say the least."
Both Professor Morgan and Professor Lucas agree there are uncertainties about who Mr Trump would choose for key cabinet and White House staff posts, as no one is sure who is around him.
While Professor Cullinane, who lectures in US History at Northumbria University and who is also an American citizen, said Mr Trump's first priority if elected will be domestic issues.
"He is going to have to worry about protests and popular unrest about his presidency," he said, suggesting if Mr Trump does make it to the Oval Office, it will be by a "narrow victory".
"Some states will be closer than others and there will, I suspect, be legal challenges to Trump's victory in those states which are particularly close," he added.
When it comes to the UK, Professor Cullinane said he does not think the British people will "open their arms to Trump immediately".
Referencing Mr Trump's recent re-use of the term "Brexit president", Professor Cullinane said he thinks he will try and align himself with Brexiteer figures in the UK.
"There will be some people he would reach out to in the British cabinet like Liam Fox," he added.
"I wouldn't be surprised if Trump is president that he does try and reach out to some of the backbenchers in the Tory party in order to try and build relations."
On trade and any deals that Mr Trump may strike with the UK, Professor Morgan warned: "I don't think we could expect any favours when it comes to trade deals.
"Trump will be what you might call a realist. I don't think he has any commitment or feelings for the special relationship."
He also said he thinks "Trump would look to develop a relationship with Putin", a sentiment echoed by Professor Lucas.
Under a Trump presidency, he said it is likely we would see a "much more uncertain relationship between the US and Russia, because we don't know if he is going to cosy up to Putin or maintain distance".
And he warned that an already badly damaged American image would "plummet even further" in some parts of the world in the event of Mr Trump becoming president.
Professor Morgan said Mr Trump being elected would almost be a last "primeval scream of white blue collar America which feels aggrieved with the establishment" for sending well-paid jobs in manufacturing abroad.
"What is interesting and horrific in some ways about this election is that regardless of what Trump says and does, it doesn't really affect his core support," he added.
"And the reason for that quite simply is that when Trump, as we see it, misbehaves or conducts himself in a fashion that has little parallels in modern American politics, that only reassures the supporters that he is not part of the establishment.
"That he is not playing the conventional political game and that he has not sold out to the media."