We are witnessing what happens to a person who is consumed with the need to dominate, but cannot.

Iran is unlikely to give in. It can withstand the economic pressure of a blockade better than Donald Trump can withstand the political pressure that comes with rising gas prices (now nearly $4.50 a gallon, on average), soon followed by rising food prices.

His looming failure in Iran is not just a serious geopolitical defeat for the United States; it’s a personal crisis for Trump.

Those rising prices coupled with an increasingly unpopular war have increased the likelihood that Democrats will take back control of the House and even possibly the Senate in the upcoming midterms.

Here again, it’s not just a political defeat for the Republican party but a personal crisis for Trump.

His ego cannot accept a humiliating loss, as we saw after the 2020 election. His need to bully, dominate and gain submission is so hardwired inside his insecure head that the defeats he’s now facing – to Iran and to Democrats – are already setting off explosions.

He’s posting more wildly than ever – attacking, insulting, ridiculing, threatening.

On Sunday, Trump posted that Democrats had “RIGGED the 2020 Presidential Election. GET TOUGH REPUBLICANS – THEY’RE COMING, AND THEY’RE COMING FAST! They’re no good for our Country, they almost destroyed it, and we don’t want to let that happen again!” He demanded that Republicans “approve all of the necessary Safeguards we need for Elections to protect the American Public during the upcoming Midterms”.

More of his posts are bizarre AI-generated paeans to himself, his godlike powers, his wished-for physique and his self-image of omnipotence. On Friday night, he posted an AI-generated image of himself, JD Vance, Marco Rubio and Doug Burgum, all shirtless and with young physiques, standing in the reflecting pool in front of the Lincoln Memorial, along with an unidentifiable woman in a bikini.

Minutes later he posted an image of the House minority leader, Hakeem Jeffries, holding a baseball bat, with a caption calling Jeffries “low IQ”, “a THUG” and “a danger to our Country”. On Tuesday, he posted AI-generated images of Joe Biden on one knee with the caption “COWARDS KNEEL”, Barack Obama with the caption “TRAITORS BOW” and himself with his fist raised and the caption “LEADERS LEAD”.

His mouth – never in control – is now in diarrheic mode. He’s even back to attacking the pope, accusing him of “endangering a lot of Catholics and a lot of people”, adding, “but I guess if it’s up to the pope, he thinks it’s just fine for Iran to have a nuclear weapon”.

His thin-skinned vindictiveness is beyond anything we’ve seen before, which is saying a lot. Last week, after the German chancellor, Friedrich Merz, said the US was “being humiliated by the Iranian leadership”, Trump repeatedly attacked and ridiculed Merz. The defense department then said it was pulling 5,000 troops out of Germany, and Trump said he was increasing tariffs on European cars and trucks to 25% (from 15%).

He’s becoming ever more obsessed with monuments to himself – his ballroom, his arch, his so-called “garden of heroes”, his Trump-embossed passports, his image on 24k gold commemorative coins, and his name plastered or etched all over Washington. His plans for self-monuments are becoming larger by the day, more grotesque, more grandiose and more expensive. Senate Republicans just proposed $1bn more for Trump’s ballroom, which, recall, was supposed to “cost taxpayers nothing”.

He has even directed the treasury to announce that his own signature – yes, the same one that appears in a book of birthday greetings for Jeffrey Epstein – will replace the treasurer’s on all new US paper currency. This will be the first time in US history that a sitting president’s name will appear on circulating cash money.

His thirst for vengeance is exploding, too. Last week the Department of Justice launched another criminal case against former FBI director James Comey (whose earlier indictment was quashed by the courts) for posting a picture of seashells spelling out “86 47” on Instagram a year ago. Trump is also insisting that the justice department restart its criminal investigation of Jerome Powell and double-down against the former joint chiefs of staff chair Mark Milley and others he considers “enemies”.

Facing the two monumental failures of Iran and control over Congress, Trump is fanatically seeking other ways to assert dominance. On Tuesday, his education department announced a civil rights investigation into Smith College over enrolling transgender students.

On Thursday, Trump demanded that Hakeem Jeffries be charged with “INCITING VIOLENCE”, linking the attempted shooting at the White House correspondents’ dinner with Jeffries’s call for a “maximum warfare” redistricting campaign in response to Republican efforts to gerrymander their states.

Regardless of what happens in Iran, he’ll claim victory. That will be difficult to do convincingly when gas prices remain more than $4 a gallon, but he’ll undoubtedly try.

What if Democrats win control of one or both chambers of Congress in the midterms and he claims they lost or cheated? The nation barely survived the last time Trump’s fragile ego faced a major loss.

We’ll also have to cope with Trump as a lame-duck president who can no longer dominate and gain submission as he did before. Will he try to remain president beyond his second term to avoid this?

The man is unwell. Seriously unwell. Lame-duck presidents fade away, but injured dictators can be dangerous.

• Robert Reich, a former US secretary of labor, is a professor of public policy emeritus at the University of California, Berkeley. He is a Guardian US columnist and his newsletter is at robertreich.substack.com. His new book, Coming Up Short: A Memoir of My America, is out now in the US and in the UK