Maybe we’re too busy laughing to see it. Perhaps it’s the jokes and memes that Donald Trump generates in abundance, the gift that keeps on giving, that blinds us to a chilling fact that we’d rather not face. Put simply, the leader of the world’s most powerful nation is behaving like an authoritarian dictator, one who threatens democracy in his own country and far beyond.

Here’s the latest example of how the comedy can distract. On Thursday Donald Trump marked the Fourth of July by praising the US military, invoking the heroism of an army that defeated the British in the 18th century in part because “it took over the airports”. Lol: behold, the ignoramus president. Cue more chuckles as Trump delivered that speech during a downpour, the Almighty himself apparently deciding to rain on Trump’s parade.

But all those giggles served to obscure the more pressing fact: that in a departure from all precedent, Trump had used Independence Day to stage a military display, in which M1A2 tanks and Bradley armoured vehicles rolled into Washington, while fighter jets and helicopters filled the sky. The generals, mindful of the need to separate military and political power, had long opposed this extravaganza and, tellingly, most of the joint chiefs contrived to stay away. They understood that such a pageant is the stuff of despots, not democrats.

Another image framed this split-screen 4 July: that of the children, separated from their parents, who are caged in detention camps on America’s southern border. Accounts by lawyers and doctors who were allowed brief visits to these hellish places are almost unbearable to read: children deprived of sleep, denied access to blankets or mattresses, not allowed to wash their hands or brush their teeth; toddlers left alone on cold, hard floors, so traumatised they sit in stunned, tearless silence. I’m especially haunted by the report of “a suicidal four-year-old whose face was covered in bloody, self-inflicted scratches”.

This too is what dictators do: demonising a group – in this case, migrants – as an alien threat, an army of invaders, so intensely and for so long that eventually any fate, no matter how brutal or inhumane, seems deserved, even when it is inflicted on that group’s youngest and most vulnerable members. Breaking up families, caging children in hot, fetid, disease-ridden camps – this is what dictators do.

Play Video 1:42 'We will plant the American flag on Mars': Trump delivers July 4th speech – video

But we hesitate to see it for what it is. Again, the laughter gets in the way. So we snigger at Ivanka Trump ludicrously barging her way into a powwow of world leaders, making a meme of #uninvitedIvanka, rather than confronting head-on the reality that Trump is doing what dictators always do: he’s building a hereditary dynasty, so that his power won’t end with his death. Those images at the G20 looked absurd to us, but they will take their place in the showreel, so that, come the 2024 or 2028 elections, they can be used as proof of Ivanka’s supposed experience on the global stage.

It’s all there, if you can bear to look at it. From the kleptocratic impulse – Trump pushing to meet foreign leaders at his hotels, so that he can profit – to his undisguised admiration for his fellow strongmen. Trump can’t get enough of Kim Jong-un, handing him another propaganda gift last weekend by setting foot in, and thereby legitimising, the slave state Kim rules so bloodily – and, once again, getting nothing in return. But in Osaka, at the G20 summit, he was also palling around with Mohammed bin Salman, even though the UN and the CIA both agree the Saudi leader was directly responsible for the violent murder of US resident Jamal Khashoggi. As for the simpering deference Trump shows Vladimir Putin, it’s a wonder Trump’s supporters describe him as a strongman at all: next to the Russian president, he looked like a teenager with a crush.

Draw up a checklist of the semiotics of dictatorship and Trump ticks every one. He muses out loud about being president for life, saying it would be “great”. He’s indicated often that he would not accept the outcome of an election he lost. He’s threatened to jail his political opponents. He has the despot’s attitude to the truth – lying routinely, even about trivial matters, partly to demonstrate power. So great is his sway over his devotees, he can make them believe even what is provably false.

And he has the despot’s contempt for a free press, forever railing against the “fake news” media and all but abolishing the White House daily briefing, which at least aimed to hold successive administrations to account. Note his abuse of power to pursue vendettas against the companies that own media organisations that displease him: seeking to raise postal charges on Amazon, as retaliation against the Washington Post, owned by Amazon’s Jeff Bezos; and moving to block the AT&T-Time Warner merger to hurt CNN.

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The most chilling moment of his encounter with Putin last weekend came when the two men bonded over their shared loathing of journalists: “Get rid of them,” Trump said to his Kremlin counterpart, perhaps envious of the toll of 26 murdered journalists notched up in Russia during the Putin years.

His disregard for the rule of law is also that of the autocrat. His aides simply ignore subpoenas to appear before Congress, while in the name of his invented migrant “crisis” at the southern border, he became the first US president ever to declare a national emergency solely to circumvent the authority granted to Congress by the constitution. “That was a pretty straightforward authoritarian power-grab,” according to Kristy Parker, a former Department of Justice lawyer now with the Protect Democracy advocacy group.

Why don’t we see all this as the behaviour of a would-be dictator? Part of it is a language problem. The archetypal despot lodged in the collective imagination does not speak English. Dub a Trump speech into, say, Italian, show it in black and white, and perhaps then we’d spot the similarity. Part of it is that Trump has not been able to do his worst. No elections have been overturned, no dissidents jailed, no journalists arrested. The restraints of the US system have, so far, kept Trump in check.

Yet that can lull us into a false sense of security, what political scientist David Runciman calls “the confidence trap”: the belief that, because democracy has withstood past threats, it will withstand present and future ones too. That’s complacent, not least because those restraints are fraying fast. Note how Trump is appointing sympathetic judges in record numbers: you can’t rely on the courts to check an authoritarian president if the courts are increasingly in that president’s image.

All this poses an urgent dilemma in the US, as Americans work out how best to hold back a president who is a menace to the constitution. Impeachment carries great political risk, even if it is the Democrats’ constitutional – and moral – duty. But Trump presents a challenge to America’s international allies too.

Like it or not, the US is the mightiest player in the democratic world. When that country is led by a would-be dictator, it undermines global democratic standards. How can the west stand up to, say, Viktor Orbán, when it indulges Donald Trump? Citizens and governments around the world need to realise that acting as if nothing has changed will not do; that Trump should not be treated as if his presidency were normal when it is nothing of the sort. But first, we need to see clearly what’s happening – and, perhaps, stop laughing.

• Jonathan Freedland is a Guardian columnist