Before Donald Trump finally surrendered in his Iran war, he declared victory several dozen times, including on day eight– “We’ve already won!” – day 10 – “The war is very complete”– day 12, proclaiming he had won five times in 13 seconds – “We’ve won, let me say we’ve won. You know, you never like to say too early you won, we won, we won the bet in the first hour it was over”– and day 39 –“Total and complete victory, 100%. No question about it”– and claimed a deal to end the war was just around the corner 38 times. The first time he raised the prospect of peace, on day 24, he said the two sides had reached “almost all points of agreement”.

Trump boldly affixed his signature with a sharpie to the Memorandum Of Understanding on day 110, 17 June, at the Palace of Versailles, where the ruinous treaty concluding the first world war was signed. He seemed oblivious to the historical symbolism of the place, but bedazzled by its gold. “Versailles is not gold leaf – Versailles is the real deal,” he remarked.

At a press conference beforehand, secretary of state Marco Rubio stood stone-faced as an Easter Island statue, perhaps hoping nobody would notice him, but still tainted with the war by his presence. Trump said about his absent vice-president, who was queasy about the whole venture but has now been assigned the task of defending it: “If it doesn’t work out, I’m blaming JD.”

The next day, Vance insisted the war was a “win” and falsely stated that lifting oil sanctions is “not a new benefit” for Iran. Trump, who invariably chooses a fall guy for his own failures, apparently does not wish to have anyone become his successor. Vance, for his part, promptly pointed at Israel, where Trump’s MOU is universally excoriated, as the fall guy. “If I was in the cabinet of the Israeli government,” Vance said, “I might not be attacking the only powerful ally that I have anywhere left in the entire world.” Vance has been delegated to drink from the poisoned chalice. Welcome to Jonestown.

That day, 18 June, Israel Hayom, the rightwing newspaper that is a mouthpiece for prime minister Benjamin Netanyahu, and is published by Miriam Adelson, who gave more than $100m to the 2024 Trump campaign, ran a lead editorial addressed to Trump: “Mr. President, you have gravely harmed the human interests of the enlightened world, and you may be remembered forever as the president who brought about America’s humiliation. You betrayed us, the Israelis. And in a single moment, the contempt you once faced suddenly seems so justified and logical.” Netanyahu, who delivered his fate into Trump’s hands, forgot that Trump abandoned even his mentor, the mob lawyer Roy Cohn, in the end.

Trump lost his war on day one. In fact, Iran first effectively closed the strait of Hormuz following US and Israeli airstrikes that day and formally closed it two days later, achieving asymmetric strategic superiority through control over a crucial spigot of the global economy. On day 43, 11 April, Trump tweeted: “The United States has completely destroyed Iran’s Military, including their entire Navy and Air Force, and everything else.” Trump could not distinguish between tactics and strategy. He confused bombs and bombast with the mission, which eluded him. The more he bombed, the more he lost the plot.

Without any strategic comprehension, Trump’s triumphalism only deepened the bitterness and anger that has followed his eventual loss. In brief, he elevated the Iranian regime into a regional hegemon and a power in the world economy; persuaded the Gulf states that the US is an unreliable ally that could not shield them; increased the influence everywhere of China; condemned Israel after Netanyahu hustled Trump into a fiasco that other presidents had carefully avoided; further alienated our European allies that prudently distanced themselves; drastically wasted US military power; and shattered US prestige. By the time he had finished, nobody on any side believed Trump should be taken at his word. The exercise of Trump exposing himself yet again as a mountebank is redundant, but now catastrophic with the whole world watching.

What Trump succeeded in obliterating was any rationale he offered for going to war. He had claimed he already accomplished regime change in Iran amidst his dire threats. On day 39, 7 April, he tweeted: “A whole civilization will die tonight, never to be brought back again. I don’t want that to happen, but it probably will. However, now that we have Complete and Total Regime Change, where different, smarter, and less radicalized minds prevail, maybe something revolutionarily wonderful can happen, WHO KNOWS?”

Trump provided his own refutation on day 110, 16 June, piling on praise for the Iranian regime that had consolidated as a theocratic military dictatorship: “You talk about regime change. I never cared about regime change. It [was] never a part … And we’re dealing with people that I think are very rational people. They were nice to deal with. They were strong people, smart people. I think actually they’re smarter than the first and second group, but they’re not radicalized and they’re, you know, looking to help their country.”

Trump is in a class of his own as an American president in launching a war of aggression without a casus belli, a direct offensive provocation, and losing it in short order. Other presidents haunted by the shadow of defeat in war knew it would discredit them. Two days after John F Kennedy’s assassination, on 24 November 1963, Lyndon Johnson told the US ambassador to South Vietnam, Henry Cabot Lodge Jr: “I am not going to lose Vietnam.” Three years later, Johnson confessed privately: “I just can’t be the architect of surrender.” “I won’t be the first American president to lose a war,” he told undersecretary of state George Ball.

President Richard Nixon uttered virtually the same words. “I’m not going to be the first American president to lose a war,” he told his aides in October 1969. Both Johnson and Nixon were undone as they struggled with their inability to end a war they did not begin but which they escalated, as the Pentagon Papers revealed, through vain attempts to achieve what Nixon called “peace with honor”.

Leaders in democracies that lose wars inevitably lose office. There is no case anywhere of a democratic leader politically surviving the loss of a war. (George W Bush was re-elected in 2004 before the defeat materialized in Iraq and Afghanistan, which by 2016 had broken the Reagan-Bush era of the Republican party and greatly contributed to the rise of Trump.) Despots historically have retained power in the aftermath of defeat only through ruthless repression, coercive control of media and scapegoating, which makes the revolt against them more explosive when it comes.

On day 107, 14 June, Trump’s birthday, Trump had announced the sketchy MOU as “complete”. “Congratulations to all!” he crowed. In a boon to Iran, Trump waived oil export sanctions, opened access to tens of billions of dollars in frozen assets, and committed to a mysteriously funded $300bn “Reconstruction Plan” that might have unspecified side deals, while entering into 60 days of negotiations to limit Iran’s nuclear program more than eight years after he withdrew from the Joint Comprehensive Plan of Action negotiated under President Obama in which Iran pledged not to develop a nuclear weapon. Trump called it a “horrible, one-sided deal that should have never, ever been made”.

On that day, his 80th birthday, Trump staged matches of the Ultimate Fighting Championship on the South Lawn of the White House in a cage under his gargantuan “claw” as though he had won the war and the fighters victorious in the ring represented his strength. His circus was the opening act of his culture of defeat and its denial.

When asked on day 111, 18 June, by an Axios reporter what insight the war had revealed to him about “the limits of his ability to exert power”, Trump replied: “There are no limits. I haven’t learned that lesson yet. I know there are, but there are no limits.” He claimed that the Iranian signing of the MOU was “probably unconditional surrender”. Trump had called for Iran’s “unconditional surrender” on day seven, 6 March.

On 18 June, Trump also declared victory over the algae blooms in the Reflecting Pool that had turned it green after he granted two no-bid contracts for $16m to a firm that previously performed pool work at a Trump golf club but had no history of federal contracting and a campaign contributor and Mar-a-Lago club member who was twice criminally convicted. The Interior Department tweeted: “The Reflecting Pool water is crystal clear, and our National Park Service team is now vacuuming up the dead algae resting on the bottom of some parts of the Reflecting Pool – just like the destroyed Iranian Navy resting on the bottom of the Persian Gulf.”

Trump said the pool would “probably” have to be drained again and accused “Radical Left Lunatics” of sabotaging his project with a knife and chemicals, though he presented no evidence. He tweeted about “terrible vandals” and “serious crimes… Years in jail!” On 19 June, the Park police arrested a 67 year-old former Olympic cyclist on a misdemeanor charge of destroying government property for reaching into the pool to touch the “American flag blue” peeling paint. He was released within hours – day 113, another quagmire, another defeat.

In 40 AD, the Emperor Caligula, notorious for his inability to “control his natural cruelty and viciousness”, as well as his “gluttony and adultery”. according to the historian Suetonius, marched his legions to the shore of the English Channel to invade Britain, where he suddenly ordered his soldiers to gather seashells as the “spoils” of war. “As a monument of his victory he erected a lofty tower, from which lights were to shine at night to guide the course of ships,” and staged a return to Rome “on his birthday in an ovation”.

Trump is now caught in his Caligula Trap from which he cannot extract himself. Mocking his self-congratulatory language, Marjorie Taylor Greene, the former Republican member of Congress and Maga queen, posted on the day Trump signed the MOU: “Congratulations to all for almost achieving peace to the war that is not a war, spending hundreds of billions of US tax dollars again for another foreign war after we voted no … This, apparently, is what winning looks like.”

• Sidney Blumenthal, former senior adviser to President Bill Clinton and Hillary Clinton, has published three books of a projected five-volume political life of Abraham Lincoln: A Self-Made Man, Wrestling With His Angel and All the Powers of Earth. He is a Guardian US columnist and co-host of the Court of History podcast