“If something cannot go on forever,” the economist Herbert Stein once said, “it will stop.” A logician would scorn this as a tautology, but it’s a useful one for contemplating all sorts of problems that never seem to end. Some things that feel like they can’t go on may continue for a very long while. The subject of Stein’s famous comment (at a 1986 economic symposium) was the national debt. Today it’s more than ten times its size in 1986, so the national debt turns out to be something that can go on—if not forever (forever’s a long time), then far longer that anyone would have believed.
But a less dismal way to read Stein’s tautological pronouncement, subsequently known as Stein’s Law, is that some things that feel like they will go on forever may surprise us by stopping. An example would be what John F. Kennedy called America’s “long twilight struggle” against Soviet communism. When Kennedy recited that phrase in his inaugural address, the struggle had already lasted 40 years (subtracting four when the United States and the Soviets were allies in World War II). By 1961 the Cold War seemed a cinch to last another century. Instead, it ended 28 years later with the fall of the Berlin Wall.
Today the bad thing that feels like it will go on forever—or anyway, for 28 more months—is the presidency of Donald Trump. Is Trump like the national debt, or is he like the Berlin Wall? Trump’s political career has certainly lasted longer than anybody (including me) could have conceived when it began in 2015, and his comeback after the January 6 insurrection was particularly unsettling. But lately I’ve started to consider that our nightmarish political epoch may end sooner than we expect. Even as some worry that Trump will defy the Constitution and run for a third term, I’ve come to doubt that he can finish his second.
My reason for thinking Trump may be like the Berlin Wall is the recent acceleration in Trump’s mental deterioration. Yes, I know that in May Trump passed his Montreal Cognitive Assessment with a score of 30 out of 30 (or anyway that’s what his doctors at Walter Reed National Military Medical Center said). I also know that while that test is said to be pretty good at diagnosing dementia, it isn’t great at detecting mild cognitive impairment. “Mild cognitive impairment” basically means grandpa doesn’t have to check in to an assisted-living facility. It doesn’t mean grandpa should be handed the nuclear codes (which apparently may reside soon inside the Arc de Trump). And mild cognitive impairment can worsen to severe cognitive impairment.
Questions about Trump’s mental capacity aren’t new. Nine years ago STAT News asked experts in neurolinguistics and cognitive assessment to compare Trump TV interviews from the 1980s and 1990s to unscripted samples from 2017. “They all agreed there had been a deterioration,” wrote the late science writer Sharon Begley, “and some said it could reflect changes in the health of Trump’s brain.” In the 1980s and 1990s Trump “spoke articulately, used sophisticated vocabulary, inserted dependent clauses into his sentences without losing his train of thought,” and so on. By 2017, Trump’s vocabulary was narrower and less polysyllabic. He repeated himself and lurched from one topic to another. The Maryland governor Martin O’Malley compared Trump’s 2016 rhetorical style to “a monkey with a machinegun.”
In 2024 a group of 225 mental health professionals said in a published open letter (bankrolled, granted, by an anti-Trump PAC created by George Conway) that Trump suffered from “malignant narcissism” and appeared “to be showing signs of cognitive decline” including “a dramatic decline in verbal fluency, tangential thinking, diminished vocabulary, overuse of superlatives and filler words,” and “exhibiting deteriorating judgment, impulse control, and motor functioning (including a wide-based gait).”
This past April a different group of mental health professionals, this time including both Democrats and Republicans, said in a follow-up statement that in the intervening 18 months Trump’s mental state had “deteriorated even further.” Among the worsening symptoms were “disorganized and tangential speech,” “unexpected sudden changes of course in strategic matters,” “episodes of apparent somnolence during critical public proceedings,” “advocacy of lethal force against civilians,” “encouragement of extrajudicial actions by armed supporters,” “seemingly compulsive, manic late-night communications—e.g., 150 social media posts in one night—fixation on perceived enemies, persecutory ideas.” One could go on, and they did:
Grandiose and delusional beliefs, including assertions of infallibility, imagery of himself as Pope suggestive of a divine mission, being a mythical warrior hero, depicting himself as combat pilot—dropping feces on civilians, and claims that his decision-making authority is unlimited—with no need to consider domestic and international laws and constrained only by his “own morality.”
I added evidentiary links here with the vague hope that some potential swing voter might click through. But I doubt many of TNR’s regular readers will bother, because none of this is exactly a secret. Imagine that President Woodrow Wilson’s stroke in October 1919, which incapacitated him until he left office in March 1921, was never hushed up by his wife and his Cabinet, but instead witnessed by the whole country. Trump’s present state is like that, only in this case it isn’t a stroke, it’s a mental unraveling. The New York Times reporter Maggie Haberman said last month that Trump spends 70 percent of his time playing Mad King Ludwig of Bavaria, gilding this, redocorating that, and building ever-more elaborate monuments to himself. Meanwhile, “the rat-a-tat of ever wilder, ever more outrageous media posts each weekend,” wrote Peter Baker in The New York Times earlier this month, “has become a fixture of the president’s second term, seen more and more as a barometer of his mental state.”
How long can this go on? Last week Thomas B. Edsall wrote in The New York Times that “no action to remove Trump from the White House will happen until he does something so threatening and damaging that drumming him out of the White House becomes an inescapable necessity.” But does anybody honestly think that day is far off?
Not me, and not most people. According to a Washington Post/Ipsos poll, belief that Trump already lacks the mental sharpness necessary to be president has risen from 43 percent in May 2023 to 59 percent in April 2026. Trump’s approval rating has been sloping downward since his second inauguration; the decline has been gradual, but consistent, with approval falling from 48 percent to 36 percent. The all-time lowest presidential approval rating in history, according to Gallup, was President Harry Truman’s 23 percent in late 1951 and early 1952. Trump’s approval rating is on track to beat Truman’s humiliating record.
Trump’s behavior will grow more erratic. Already Trump’s children are frantically stuffing their pockets with cash as if this bonanza could end tomorrow. If the midterms are as catastrophic for Republicans as political professionals expect, Trump’s political sway over his party will weaken dramatically, along with his ability to do mischief. Everything we know about Trump tells us he will not take that well. He’ll deny the midterm results as he denied the 2020 election, and will probably attempt some chicanery to keep newly-elected Democratic House and Senate members from being seated. I believe he will fail. But whether he succeeds or fails, anything Trump does to further subvert democracy will drive his approval ratings down further, and drive further upward the public’s conviction that he’s lost his marbles.
There is a point at which Trump’s approval number will fall so low, and make Trump such a liability to fellow Republican officeholders, that they’ll move to get rid of him. I don’t know what that number is, but I expect he’ll reach it during the first half of 2027. The mechanisms to get rid of Trump are pressuring him to resign, as Republicans did to Richard Nixon in 1974, or impeaching him, as has occurred twice already with Trump. Getting Trump to resign will be at least as difficult as wrestling the car keys away from grandpa. So probably the mechanism will be impeachment in the House and conviction in the Senate, and this time I think the necessary 67 Senate votes will be gettable. Among other benefits, moving Trump out will allow the GOP to run JD Vance as a presidential incumbent, which is probably their best shot at holding the White House in 2028. There’s a decent chance Vance won’t be able to wash off the stink of Trump and will lose, as Gerald Ford did in 1976. But that’s getting ahead of ourselves.
This scenario may strike you as implausible. But before you dismiss it as fantasy, show me a more plausible scenario in which an increasingly gaga Trump remains president until January 2029. When I try to imagine that, my mind just goes blank.
