Americans watching this address tonight have seen the recent images of violence in our streets and the chaos in our communities. Many have witnessed this violence personally, some have even been its victims. I have a message for all of you: the crime and violence that today afflicts our nation will soon – and I mean very soon – come to an end.”

These were the words of Donald Trump, not in May 2020 but July 2016, as he accepted the Republican presidential nomination at the national convention in Cleveland. For many observers, there was a distinct echo of Richard Nixon’s 1968 acceptance speech – “We see cities enveloped in smoke and flame” – and a foreboding that history could take a newly dark and dangerous turn.

For three years, the first president elected without political or military experience rode his luck and skirted past disaster. In the fourth year, the fates demanded payback.

Not even Trump’s harshest critics can blame him for a virus believed to have come from a market in the Chinese city of Wuhan, nor for an attendant economic collapse, nor for four centuries of slavery, segregation, police brutality and racial injustice. But they can, and do, point to how he made a bad situation so much worse. The story of Trump’s presidency was arguably always leading to this moment, with its toxic mix of weak moral leadership, racial divisiveness, crass and vulgar rhetoric and an erosion of norms, institutions and trust in traditional information sources. Taken together, these ingredients created a tinderbox poised to explode when crises came.

Trump, they say, was uniquely ill-qualified for this moment. He tried to wish away the threat of the coronavirus and failed to prepare, then paid paid no eed to how communities of colour bore the brunt of its health and economic consequences. As unrest now grips dozens of cities, he speaks an authoritarian language of “thugs”, “vicious dogs” and “when the looting starts, the shooting starts”.

The nation waits in vain for a speech that might heal wounds, find a common sense of purpose and acknowledge the generational trauma of African-Americans. That would require deep reading, cultural sensitivity and human empathy – none of which are known to be among personal attributes of Trump, who defines himself in opposition to Barack Obama.

“He is obviously in way over his head ,” said LaTosha Brown, a civil rights activist and co-founder of Black Voters Matter.

He doesn’t have a clue. He’s a TV personality. He has a cult following that’s centred around this white power broker persona rooted in white supremacy and racism. Wherever he goes, he carries that role and that kind of persona, but ultimately right now with what we’re looking for in this country is real leadership. He is incapable of providing that because that’s not who he is.”

Brown added: “He’s a personality. He’s used to these dog whistles and, instead of trying to uproot division and seeing that the citizens are actually in pain and hurting, he doesn’t have the capacity to address that. He actually adds fuel to the flames and shows how fundamentally intellectually disconnected he is from what is happening and also how ill-prepared he is as a leader to respond to that.”

Trump is not so much a child playing with matches as an arsonist hellbent on burning it all down, Brown warned: “He’s willing to kill democracy. He is willing to kill any sense of real respect or trust in his government. He is willing to kill America’s international and global relationships. He is a destroyer.”

The president’s suggestion of moral equivalence between white nationalists and anti-fascist protesters in Charlottesville, Virginia in 2017 failed to loosen his grip on the Republican party. Perhaps it tightened. At the start of this re-election year, feeling emboldened by his acquittal in a Senate impeachment trial and a robust economy, Trump was confident of his re-election chances.

Now, with health, economic and social crises feeding off each other, polls show him trailing rival Joe Biden. But the situation remains volatile and unpredictable. The president has sought to scapegoat anti-fascist protesters, and there would be little surprise if he returned to Nixonian law-and-order rhetoric to rally Republicans and lay a trap for Democrats, portraying them as “soft on crime”.

Biden has billed the election as a battle for the soul of the nation – the potential to lurch deeper into disarray with a second Trump term, or to reset, rebuild and plot a new direction. The stakes keeps getting higher by the day.

DeRay Mckesson, a leading voice in the Black Lives Matter movement, said: “Nobody’s a magician, so I don’t expect Biden to change everything on day one, but the demands should be for him to change as much of this by the end as humanly possible.

“If Trump has reminded us of anything, it’s that the government can move as fast as it wants to and nobody, no person of colour, no poor person is going to win if Trump is the president again. So I’m not interested in Trump. I am interested in a plan from Biden’s team around ending police violence. I think that needs to come now. I think it is, frankly, late, and I’m hoping to see it soon.”

Trump’s unconventional inaugural address in January 2017 is best remembered for a single phrase: “American carnage”. His entire presidency may be remembered for it too.