President Hassan Rouhani of Iran got it right on Tuesday. He said that the White House is “afflicted by mental retardation and doesn’t know what to do”.

Donald Trump’s new sanctions may not be as “outrageous and idiotic” as Rouhani claims, but we’ve now reached a stage where the American president’s mental incapacity is plain for all to see. It is a sign of the times – our times, I’m afraid – that all the rantings and ravings of Iran’s leaders over the past 40 years at last sound clear cut, true, absolutely on the cue. Trump is crackers, barmy, off the wall, categorically lunatic.

Rouhani is a sane man, but in the past we could listen to folk like President Mahmoud Ahmadinejad, who was crackers, and take a chuckle at Iran’s expense. Talk of the “Great Satan” could even get a bit boring after a while. But Trump, while possessing some of the characteristics of Colonel Gaddafi, now sounds like Ahmadinejad. The only thing he has left to say – as Ahmadinejad claimed – is that a holy cloud hung over his head when he addressed the United Nations.

But wait. It’s sure to come. God’s work looms high in the brains of the evangelical Republicans. And Trump has now proved that he can be as batty as any Middle East autocrat.

Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Show all 30 1 /30 Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Members of the Proud Boys, a fascist group, jeer at anti-Trump protesters outside of the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A supporter dressed as Uncle Sam poses at Uncle Sam Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A baby blimp rears its head amidst a group of anti-Trump protesters outside the president't campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam President Trump addresses supporters at the launch event of his 2020 election campaign in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Proud Boys have adopted Fred Perry polo shirts as their uniform and many members have the name of the group tattooed on their arms Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A line of police officers separate opposing groups of protesters outside the launch of President Trump's 2020 campaign launch Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A protester hits a Trump punching bag during a protest outside Trump's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Twin Trump supporters pose for a photo at the president's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A protester dressed as a caricature of Donald Trump stands outside the president's 2020 campaign launch in Orlando, Florida AP Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A Trump supporter faces off against a protester outside the president's campaign launch in Orlando, Florida AFP/Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A Proud Boy shouts across the police line at anti-Trump protesters outside the president's campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A Trump supporter poses for a photo at the president's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A Proud Boy jeers at anti-Trump protesters who are separated from the president's supporters by a police line outside the president's campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A man dressed as Uncle Sam poses at President Trump's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam An anti-Trump protester faces off against a supporter outside the president's campaign launch in Orlando, Florida AFP/Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Members of the Proud Boys, a fascist group, jeer at anti-Trump protesters outside of the president's 2020 campaign launch Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A child holds a 2020 US "dollar bill" that features Donald Trump's face at the president's 2020 campaign launch EPA Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Anti-Trump protesters rally outside the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Anti-Trump protesters rally outside the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Numerous baby Trump balloons are raised in protests outside of the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A supporter wears a T-shirt depicting Trump as a hero at the president's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam President Trump addresses supporters at the launch event of his 2020 election campaign in the Amway Centre in Orlando, Florida AFP/Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam An anti-Trump protester calls for the president to be impeached outside the launch event for his 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Supporters of Donald Trump face off against protesters outside of the president's 2020 campaign launch in Orlando, Florida AP Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A baby blimp rises behind a group of anti-Trump protesters outside the president's campaign launch in Orlando, Florida AP Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A supporter dressed as Uncle Sam poses at President Trump's 2020 campaign launch in Orlando, Florida AP Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A member of the Proud Boys, a fascist group, holds a sign up outside of the president's 2020 campaign launch in Orlando, Florida AFP/Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam A supporter bears a Trump flag at the president's 2020 campaign launch in Orlando, Florida Reuters Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam Protesters hold baby Trump balloons in the rally outside of the president's 2020 campaign launch in Orlando, Florida Getty Trump 2020 launch: Fascist Proud Boys, baby blimps and Uncle Sam An anti-Trump protester holds a sign accusing the president of being a traitor Getty

I can even remember the day, early in his presidency, when I said in an Irish radio interview that Trump was “insane”. In those days, this was considered a little too provocative and my interviewer muttered something along the lines of “Well, Bob, you don’t have medical qualifications.” The difference now, of course, is that the world knows that the White House is a mad house. (My reply to my Irish colleague, by the way, was that if I had claimed Trump to be completely sane, he would not have queried whether I could say that without being a doctor.)

No matter. We have Jared Kushner trying to give the Palestinians cash rather than a state, apparently still backed up at his Bahrain bash by the autocrats of the Arab Gulf. To see Tony Blair, one of the west’s biggest failures in the Middle East, trying to teach the bizarrely overconfident Kushner that there’s got to be a state for the Palestinians as well as the $50bn “Peace to Prosperity” plan was only matched by Kushner’s ridiculous property developer’s talk about “issues” and “negativity”. The longest foreign occupation in modern history, of the West Bank by the Israelis, does indeed throw up a number of “issues” – such as the massive property theft for Israel’s colonial expansion project – which do cause quite a lot of “negativity”.

I do sometimes wonder if this weird sequence of events, not to mention the destruction of America’s more-than-$120m drone by Iran, has been set in motion by a massive collapse of mental integrity and ability in the west – not just in America, but in Europe as well.

There are many causes for this to have happened, but I suspect we were all somehow so overconfident of our democracies that we took them for granted. How on earth, I keep asking myself, could a bounder like Boris Johnson be the likely next British prime minister when his own stewardship as foreign secretary was so filled with errors of judgement, not least in the Middle East?

It’s enthralling to read the words of two of Ireland’s top journalists and commentators because they often have a freshness somehow lacking in the Brexit debate in the UK. Last week, for example, we had Fintan O’Toole, one of the finest chroniclers of our time – he is the Philosopher King of The Irish Times – saying that “if lies were flies, the swarm around him would be so thick that Boris Johnson would be invisible” and Johnson’s voice would be “drowned out by their incessant, deafening hum”.

O’Toole suggested there was “ordinary political lying” (evasions, circumlocutions, omissions, half truths) “and then there is Johnsonian lying – bare-faced, full-throated, unabashed”. The columnist asked if British people are so sick of the first kind of dishonesty “that they actually find Johnson’s upfront mendacity refreshing”.

And then there was economist and writer David McWilliams, who reminded readers that great political parties don’t have permanent life insurance – the old Liberal Party of Gladstone was eclipsed by the Labour Party, and the Irish Home Rule Party was wiped out by Sinn Fein at around the same time – and added that “watching the Tory leadership debate … it looks like the next Conservative prime minister could be the last. Indeed, going further, the next prime minister of the UK could conceivably be the last prime minister of the UK.”

Ouch. Maybe McWilliams should also have discussed how Republican and Democratic parties in the US can no longer take eternal life for granted?

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Perhaps what makes Britain’s comic opera and America’s more dangerous Wild West show so similar is the immense damage which their leaders are doing to their own countries by making them “great again”. Perhaps it is because I am just finishing the first volume of the life of an infamous German dictator – a magnificent work of scholarship by Volker Ullrich – that I draw up with concern at the repeated assurances he made of Germany’s greatness being “restored” and its future secured without “aliens”.

I am not, of course, comparing the little Austrian ex-corporal with the funny moustache to Messers Trump or Johnson. However there was in German politics, before the collapse of the Weimar Republic, a parallel mendacity on the part of the Nazis, of public claims and secret agreements, and the same cynicism towards “old fashioned” democracies.

We are not approaching a Weimar moment in Britain or America. Or Italy. Or Hungary. Or Poland. (Though I wouldn’t be so sure about the last two.) But at least it might be comforting to the people of the Middle East to realise that their own pitiful autocrats, with equally outrageous lies, are no longer entirely out of sync with world powers.

The health of Trump was recently described by Dr Lance Dodes, retired assistant clinical professor of psychiatry at Harvard Medical School, as “a dangerous sociopathic disorder”.