In the general relief that has followed the midterm elections, we’ve been hearing that Donald Trump is losing his grip on the Republican party and that his popularity with the electorate has waned. The evidence seems clear: most, if not all, of the candidates he backed in crucial political races were defeated, as were the far-right extremists and the 2020 election deniers.

It’s hard not to be cheered by the indications that the country hasn’t entirely lost its collective mind. But to “move on” from Trumpism, to view his regime as an aberration, a four-year mistake, is to fall victim to the dangerous historical amnesia to which Americans seem so susceptible.

Even as we celebrate Trump’s failure to push Dr Oz to victory in Pennsylvania, we need to remember what our 45th president did, how effectively and recklessly he tapped into and unleashed our dark side, and the wellsprings of cruelty and hatred. We need to recall the broken-marionette twitches with which he mocked a disabled journalist and encouraged the crowd to laugh, his leading the chants demanding that Hillary Clinton be incarcerated – and his speech inciting his supporters to punish Mike Pence for refusing to decertify the 2020 election.

Surely I’m not the only person who remembers the night when teams of immigration lawyers rushed to New York’s JFK airport because Trump had just called for all Muslims to be prohibited from entering the country, or the vicious nicknames he invented for his enemies and opponents, or his refusal to condemn the neo-Nazis who marched in Charlottesville. We are still mourning the thousands who died needlessly after Trump politicized a virus. We haven’t had time to forget how close his policies – and his spirit – have edged our democracy to the brink of extinction, and few of us feel certain that, even now, we are safe and in the clear.

But just in case we’d forgotten any of that, just in case we’d persuaded ourselves that our Donald Trump problem is over, Trump’s announcement of his intention to run for president in 2024 brought it all back. The boasting and lying haven’t stopped. He claimed to have “taken decisive action” against Covid-19, to have more or less single-handedly defeated Isis, to have brokered a deal compelling Central America to take back deported gang members, and (despite the facts still fresh in our minds ) to have scored huge successes in helping elect candidates in the midterm elections.

It was painful to be reminded of the characteristically wild and inflammatory hyperbole (our cities, he claimed, are “cesspools of blood”), the vindictive attacks on the FBI and the Department of Justice, the winking reference to Barack Hussein Obama, and the racism and jingoism, the hatred of immigrants conveyed in his warnings about the “hundreds of millions” of criminal “savages” crossing our border for “a bad and sinister reason”. Once more, we heard his smarmy mocking of our concerns about the environment and the future of the planet, his derision of “the socialist disaster known as the green new deal”, his suggestion that we expand our mining for coal and drilling for fossil fuels.

Meanwhile he seemed to have found some harsh new notes to sound. He suggested that drug dealers be summarily executed following the “quick trials” that work so well in China, that congressional term limits be abolished, that voting be made more difficult, that critical race theory and “gender insanity” be banned from the schools, that “parental rights” be upheld and that trans rights – which he characterized as “men playing women’s sports” – be weakened or abolished.

It was all too familiar – and disturbing. When he spoke of reclaiming the “corridors of power”, it was hard not to think of the insurrectionists surging through the corridors of the US Capitol. And at moments it did feel as if he were reprising the tone and substance of the January 6 address – the appeal to take back our country – that sent his loyal followers on their destructive course. In a speech that lasted over an hour, less than a minute was spent promising to bring the country together; the rest of the time was devoted to inspiring an even greater divisiveness, a sharper awareness of difference, of the gap between “us” and “them”.

But perhaps the most upsetting thing was Trump’s hammering insistence on the “fact” that America has been all but irreparably broken by the “radical left trying to destroy our country from within”. That was the theme that emerged most often as he spoke: our country is a “laughing stock”, a nation in “disarray” and “ruin” – a historical catastrophe from which he alone has been sent to save us.

If we think we’ve heard it before, it’s because we have – long before Donald Trump entered the political arena. It’s the rhetoric of fascism and authoritarianism, the idea of a country that has been undermined, sabotaged and stabbed in the back, and that can only be rescued from certain destruction by the intercession of a dictator.

• Francine Prose is a former president of Pen American Center and a member of the American Academy of Arts and Letters and the American Academy of Arts and Sciences