Ninety minutes is a lifetime in politics these days – and Wednesday's reality TV show let us know that it was 90 minutes of our lifetimes we will never get back. A horrible, disastrous, useless session that left viewers utterly disappointed – the worst debate in modern American history.

President Donald Trump hates being challenged, and he gamed this debate to occupy the platform and bully former vice-president Joe Biden and the moderator, Chris Wallace, to recreate his favourite playing field: where he owns the oxygen and sucks it out of the room. He loved all those precious minutes where he could soar unfettered because, in the words of an Australian prime minister he does not know, "I'm going to do you slowly, mate." Trump lashed Biden for being a Trojan horse for socialism, anarchy, crime and much, much worse.

President Donald Trump hates being challenged, and he gamed this debate to occupy the platform and bully former vice-president Joe Biden and the moderator, Chris Wallace, to recreate his favourite playing field: where he owns the oxygen and sucks it out of the room.

Going into this first debate, the polls and the fundamentals underpinning Biden's campaign were steady. Nationally, he is up by seven to 10 points against Trump, and is constantly registering more than 50 per cent of voters polled - a significant benchmark. He is leading in every crucial swing state, and competitive even in Republican redoubts Iowa, Georgia and Ohio. Women voters are for Biden over Trump 65-35 – up 15 points over Hillary Clinton's margin.

Trump's approval is at 43 per cent. No president has won re-election while under 50 per cent – a benchmark Trump never reached in his term. He is carrying white voters 52-46, but in 2016, he won them by 16 points.

Biden leads with older voters 52-37; Trump won them by seven points in 2016. Sixty per cent of Americans do not want the Supreme Court to outlaw abortion – but this is a major driver for Trump to place judge Amy Coney Barrett on the court by election day. At 57 per cent approval, Obamacare is more popular than Trump.

So Trump had to take Biden apart, and rev up the engine that won those key states that delivered the presidency to him in 2016 with only 46 per cent of the popular vote, against Clinton's 48 per cent. Trump only plays offence – never retreats into defence.

Biden struggled under the onslaught – to get heard, to keep focused on issues as Trump changed the subject – and was out-talked. Biden could not proceed for more than 30 seconds without Trump interrupting.

Trump was pugnacious in the extreme, but Biden does not fight on those terms, and was hurt. Trump absolutely cemented his base with his performance. They loved it. Biden supporters came away sickened by the President as much as ever. This debate left the country as divided as ever on their leadership and their future.

Biden struggled under the onslaught – to get heard, to keep focused on issues as Trump changed the subject – and was out-talked. Biden could not proceed for more than 30 seconds without Trump interrupting.

But was Biden's performance strong enough to bring him to victory over the last 34 days of the campaign? His enthusiasm factor is much weaker than Trump's. Sixty-five per cent of the Trump base is "very” enthusiastic for their President, but only 49 per cent are similarly amped up for Biden. That was probably unchanged after this debate. If all of Trump's supporters show up to vote and 10 per cent of Biden's stay home, trouble for Joe.

Biden's Hispanic vote is not especially strong, and this could cost him Florida, where Hispanics who hold enmity for the regimes in Cuba, Nicaragua and Venezuela are firmly behind Trump and his animus for the dictators their families fled.

The projected African American vote for Biden will be greater than Clinton's in 2016 – but lower than Obama's in 2012.

There are wildcards that could come into play. No one is immune from coronavirus. If Trump or Biden gets sick, that will change the race. If Biden stumbles physically or mentally, this could raise doubts about his abilities for the presidency.

And sadly, there is a prospect of violence. The days before the election will be the most tense the country has faced since the September 11 terrorist attacks in 2001. The mood is grim – and was not at all helped by this Trump-Biden encounter.

In the decade from 1963-72, horrific political violence was rampant, from the assassinations of president John F. Kennedy, Martin Luther King and Robert F. Kennedy, and the attempt to kill governor George Wallace of Alabama as he campaigned in 1972 on a white supremacy, law-and-order platform. Candidates for the presidency have not been attacked since. The danger today is an America with too much ugly anger and too many guns.

Trump and Biden will meet two more times. But with 90 million tuned in, this was the one that counted most. It disappointed and reinforced the terribly sad state of American democracy. Hope was mugged on the debate stage in Ohio.