As the president rants about buying Greenland and battling China, some say the TV presidency has finally jumped the shark

“I am but mad north-north-west,” declares Hamlet. “When the wind is southerly, I know a hawk from a handsaw.”

Trump seems to think he's an emperor – but we are not entertained Read more

The prince of Denmark’s pronouncements raise questions over his fitness for the throne. But they might seem a little less unhinged when compared to the ramblings of another blond this week.

Donald Trump took umbrage when the Danish government dismissed his notion of buying Greenland as “absurd”, retorting that its prime minister’s reaction was “nasty”. Outlandish as it seemed, this was just one example in an epic session of delirious, dizzying verbal jazz that left some sincerely questioning the president’s mental state.

On MSNBC, the host John Heilemann summed up for viewers of Deadline White House: “A full 24-hours after a sustained presidential performance that even by Donald Trump’s standards qualified as unusually madcap, manic, unhinged and unnerving, the world is reeling and offering a collective judgment of ‘OMG and WTF’…”

Hamlet’s madness can be sourced to the murder of his father by his uncle. Trump’s was reportedly attributable to warnings of American economic demise. The businessman who made promises of growth, stability and “jobs jobs jobs!” the raison d’être of his political candidacy is said to have been rattled by portents of a recession that would cloud his bid for re-election in November next year.

He is in a new phase of his behaviour and it’s not one that lends a lot of confidence that Donald Trump is a well man Rick Wilson

Trump was forced to confront the prospect that his fatal flaw – the obsessive waging of a trade war with China – could bring about his own downfall.

Such was the air of desperation at the White House on Friday that Trump launched a Twitter rant against Beijing, issuing a Soviet-style command beyond his writ that send markets plunging: “Our great American companies are hereby ordered to immediately start looking for an alternative to China, including bringing … your companies HOME and making your products in the USA.”

He also renewed his attacks on Jerome Powell, the Federal Reserve chair, who indicated unwillingness to cut interest rates to bolster economic growth. “My only question is, who is our bigger enemy, Jay Powell or Chairman Xi?” Trump demanded, going on to announce fresh retaliatory tariffs.

The outburst capped a wild week even by the standards of a president about whom everything has been said before – which in turn has also been said before. It consisted of claims of escalating wackiness combined with reassurances about the health of the economy that appeared so strained they brought to mind a line spoken by Gertrude, Hamlet’s mother: “The lady doth protest too much.”

On Wednesday, for example, talking to reporters before departing on the Marine One helicopter from a sweltering White House south lawn, Trump began: “So, the economy is doing very, very well … Our economy is the strongest in the world, by far. Nothing even close.”

Play Video 1:01 What Greenlanders say about Trump's interest in their country – video report

In the ensuing 35 minutes, Trump parroted gun lobby talking points on background checks, reversed his position on a payroll tax cut, called for Russia to rejoin the G7, derided the former vice-president Joe Biden as “Sleepy Joe”, blamed the media for trying to bring on a recession and falsely claimed about immigration policy: “President Obama and others brought the families apart, but I’m the one that kept the families together.”

There was more. Trump repeated his use of an antisemitic trope – “In my opinion, you vote for a Democrat, you’re being very disloyal to Jewish people and you’re being very disloyal to Israel” – and suggested divine providence had chosen him for an escalating trade war with China, insisting with a skywards glance: “I am the chosen one.” The president later said that was sarcastic but he had also recently quoted a radio host declaring that Israeli Jews love him as if he were the “King of Israel” and “the second coming of God”.

He also renewed his attack on Denmark, a key Nato ally. Although he is not the first president to float the idea of buying Greenland – Harry Truman considered it in 1946 – and thereby expanding the size of the US by more than a fifth, Trump’s decision to abruptly cancel a state visit to Denmark out of spite, then insult the Danish prime minister, Mette Frederiksen – “You don’t talk to the United States that way, at least under me” – left diplomats slack-jawed.

‘Very much a different character’

All told, it was perhaps the week in which The Trump Show, now in its third season, finally “jumped the shark” – a reference to the 1970s sitcom Happy Days, in which the character Fonzie jumps over a shark while on water-skis, seen as a gimmick by script writers desperately short of ideas. Former Trump administration officials told the New York Times they are increasingly worried about the president’s behaviour, especially as there are now few seasoned advisers to constrain him.

Rick Wilson, a Republican political strategist, told the Guardian: “I think it is demonstrable that he is getting worse. I think that the continuous verbal aphasias, the lack of coherence, the obvious anger, the sort of inability to conform his affects to the times and places he is appearing have led a lot of people who have been observing him for a while now to note that he is in a very new phase of his behaviour and it’s not one that lends a lot of confidence that Donald Trump is a well man.”

Play Video 0:48 Donald Trump says he is 'the chosen one' to take on China – video

He added: “A meaningful fraction of Americans at first viewed it as sort of amusing or as just a funny affectation and as part of his super clever negotiating skills but more and more people are looking at it as, there’s something wrong with this man, there’s something very off now about him. Even if you look at video of two years ago, he is very much a different character then he was in this in the ’16 campaign.”

Trump is known to brazen out every crisis, perpetually brash and self-confident. But the economy is arguably his Achilles’ heel.

The economy is at least one, maybe two, maybe even three legs of the Trump table Bill Whalen

The Washington Post reported: “Through the week, White House officials became increasingly agitated that the public sentiment about the economy seemed to be tipping. Trump, aides said, is obsessed with media coverage of the economy, and thinks Americans will believe negative news and stop spending money. This exasperation began several months earlier.”

Wilson, the author of Everything Trump Touches Dies and a Daily Beast article headlined “This Isn’t the Madman Theory. This Is a Madman President”, agrees that recession talk might be a causal factor in Trump’s downward spiral.

“He plays a strong man on television,” he said. “The character he played on The Apprentice is what most Americans voted for and they thought of him as a strong negotiator and a bright person and a person with integrity and mental discipline and strength. But that was a TV character, that’s not the real Donald Trump.

“The real Donald Trump is a narcissistic person and a weak person and a person who lacks personal discipline on almost every axis and so what’s happening, as he feels the mighty pressures of the presidency, is ugly. He doesn’t have the cognitive ability or the bottom to handle the pressures he’s under and so it’s gotten to be this extraordinarily ugly picture of a man who’s very much out of control.”

Trump will be all too aware that after more than 10 years of growth, the economy seems to be showing vulnerability. Factory output has fallen and consumer confidence has thinned while markets have been volatile, although unemployment stands at just 3.7%.

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Since the civil war, only one president has won re-election with a recession in the final two years of his first term. For voters willing to stomach Trump’s personality and policies as long as the economy is humming, it could be a deal breaker.

Rick Tyler, a political analyst, said: “What else do you have? Do you have peace in the Middle East? Do you have a denuclearised Korean peninsula? Do you have peace and harmony among the races?”

Bill Whalen, a research fellow at the Hoover Institution thinktank at Stanford University in Palo Alto, California, said: “The economy is at least one, maybe two, maybe even three legs of the Trump table.”

Not even the president’s career-long expertise in deflection and distraction can necessarily save him this time. Gwenda Blair, a Trump biographer, said: “How about building a wall? But it never happened. How about buying an island and adding a new state? That would be pretty cool.

“He’s dancing as fast as he can. Gravity will trump Trump. It is inevitable. Will it be before November 2020? That is the question.”