Behold, the girther movement. Like those “birthers” who followed Donald Trump’s lead in denying that Barack Obama was born in the United States, the girthers refuse to believe the official account – in this case, the readout supplied by the White House doctor on Tuesday who declared, following his first such examination of Trump, that the president weighs in at 239 pounds.

The girther movement: is Donald Trump fatter than the White House doctor says? Read more

No sooner had Dr Ronny Jackson delivered his verdict than the online conspiracy theories were proliferating. How could Trump possibly weigh the same as assorted top athletes who, like him, are also 6ft 3in (1.90 metres) tall? Indeed, how reliable is that 6ft 3in figure, given that Trump’s 2012 driver’s licence gives his height as 6ft 2in? Had the doctor added an inch to Trump’s height in order to ensure that his body mass index showed him as merely “overweight”, like 34% of all Americans, a handy one pound below the threshold that would have classified him as “obese”, like 35% of Americans? (Unlikely, said former Obama adviser Dan Pfeiffer, who praised Dr Jackson, who also served in the Obama administration, as a “phenomenal doctor”.)

Others chose to focus on the Montreal Cognitive Assessment, which Trump had passed with full marks, scoring 30 out of 30 on a series of tasks that typically includes recognising a camel or drawing a clock set to a particular time. Such a test – which the president will no doubt trumpet in the coming days as proof that he is a medically certified genius – does not, they insisted, measure neurological function. It therefore could not answer the questions raised by Michael Wolff’s Fire and Fury, which paints a picture of a president unable to concentrate for more than a few seconds and whose own aides believe he has “lost it”.

Elsewhere there was simple disbelief that Trump – who, according to Wolff, retreats to his bed at 6.30pm to munch cheeseburgers and fries, who has long disdained exercise and who, Dr Jackson reported, sleeps for only four or five hours a night – could be pronounced as in “excellent” health, with his heart said to be in particularly good condition. When Jackson added that, had Trump eaten more healthily over the last 25 years, “he might live to be 200,” one wondered if the physician had succumbed to a bad case of Trump hyperbole, an ailment that does seem to be infectious.

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But all this scepticism is, in fact, a symptom of disappointment. Trump’s opponents were hoping that the good doctor might make their dreams come true, and declare the president to be such a gibbering wreck that he was unfit to serve and that it was time to trigger the 25th amendment which allows for his removal on medical grounds.

I understand that fantasy all too well. (It forms the starting point of To Kill the President, the thriller written by my alter ego Sam Bourne.) But a fantasy it remains. And it is not the only one.

Plenty of Trump-haters are pinning similar hopes on the special counsel, Robert Mueller, hoping he will be the white knight who rides to America’s rescue, revealing the killer facts about collusion with Russia that instantly eject Trump from the White House.

But the truth is, there are no quick fixes. Even if Jackson or Mueller came up with devastating findings, the act of removing Trump will fall to the Congress, currently in the hands of a Republican party that shows no appetite for standing up to the president. That’s what will have to change – which means Democrats doing the hard work of winning this November’s midterm elections. Neither the Feds nor a doctor in a white coat will do it for them: Americans will have to end this nightmare themselves.

• Jonathan Freedland is a Guardian columnist