US President Donald Trump and Democratic nominee Joe Biden on Thursday night had a second round of debate that many characterised as more civil, compared to the first one held a few weeks back.

This time round, Trump and his challenger Biden, engaged in a more substantial exchange, in which they disagreed over the battle against coronavirus, among other topics.

This is the final debate ahead of the presidential vote that is slated on November 3, though millions of Americans have already voted in early voting. 

The president declared the virus, which killed more than 1,000 Americans on Thursday alone, will "go away.” Biden countered that the nation was heading toward "a dark winter.”

"Anyone who is responsible for that many deaths should not remain as president of the United States of America,” Biden said.

After his repeated interruptions in a previous debate, Trump was more measured in tone in last night's presidential debate which took place in Nashville, Tennessee.

Trump claimed a vaccine could be ready this year, although there was "no guarantee”.

"We’re rounding the corner,” he said, adding that people were "learning to live” with the virus. 

Biden interjected: "He says . . . we’re learning to live with it. People are learning to die with it.”

Race 

Both candidates said they understood why black and brown families had to tell their children they could be discriminated against, including by police, but accused one another of being racist.

Former Vice President Biden accused President Trump of halting progress toward equality.

"I am the least racist person in this room,” Trump said, citing the criminal justice reform that his administration worked with congress to pass. 

"With the exception of Abraham Lincoln, possible exception, but the exception of Abraham Lincoln nobody has done what I’ve done,” Trump praised his work.

Biden responded: "Abraham Lincoln here is one of the most racist presidents we’ve had in modern history, he pours fuel on every single racist fire.” 

Trump accused Biden that he had helped shepherd the 1994 crime bill. 

He accused Biden of using the term "super-predator" to describe minority youths in trying to sell his tough-on-crime proposal that he shepherded into law when he was in the U.S. Senate and serving as the chairman of the Senate Judiciary Committee.

"You have done nothing other than the crime bill, which put tens of thousands of black men mostly in jail,” Trump said.

But it turns out that it was then-First Lady Hillary Clinton who was best known for using the phrase "super-predators" in the context of advocating for the crime bill, which was supported by many Democrats at the time amid concerns about persistently high crime. 

Climate change 

Biden and Trump offered different visions of climate change, with Biden saying it is "an existential threat to humanity” and Trump touting his decision to remove the United States from a global climate pact.

"I do love the environment, but what I want is the cleanest, crystal-clear water, the cleanest air,” Trump said, before saying that the economy would be hobbled by committing to stricter global standards.

"But here’s what we can’t do. Look at China. How filthy it is. Look at Russia, look at India. It’s filthy. The air is filthy,” Trump said. "The Paris accord. I took us out because we were going to have to spend trillions of dollars and we were treated very unfairly … It would have destroyed our businesses.”

Biden, speaking next, said that "global warming is an existential threat to humanity. We have a moral obligation to deal with it.”

Citing scientists, Biden said there was a limited amount of time.

"We’re going to pass the point of no return with the next eight, 10 years,” he said. 

"Four more years of this man, eliminating all the regulations that were put in by us to clean up the climate … will put us in a position where we are going to be in real trouble," he added.

Biden, who has committed to rejoining the Paris climate accord, said his plans would create new jobs in remaking the clean-energy industry.

"The whole idea of what this is all going to do, it’s going to create millions of jobs and it’s going to clean the environment. Our health, and our jobs, are at stake.”

Message to voters 

The final question of the debate drew a stark distinction between the two candidates. Both were asked what they would say to the American people, including those who didn’t vote for them, at their inauguration.

Trump said economic success will unify the country but warned that won’t happen under Biden. 

"We are on the road to success. But I’m cutting taxes and he wants to raise everybody’s taxes, and he wants to put new regulations on everything. He will kill it,” Trump said. 

"If he gets in, you will have depression the likes of which you’ve never seen. Your 401(k)s will go to hell, and it’ll be a very, very sad day for this country.”

By contrast, Biden answered the question as asked, speaking directly to Americans about how he will be a president for all.

"I will say, I’m an American president. I represent all of you. Whether you voted for me or against me. And I’m going to make sure that you’re represented,” Biden said. 

"I’m going to give you hope. We’re going to choose science over fiction. We’re going to choose hope over fear. We’re going to choose to move forward because we have enormous opportunities to make things better.”

"And I’m going to say, as I said at the beginning, what is on the ballot here is the character of this country, decency, honor, respect, treating people with dignity, making sure that everyone has an even chance,” Biden concluded. "And I’m going to make sure you get that, what you haven’t been getting in the last four years.”

The two men were supposed to have three debates, but the head-to-head set for October 15 was cancelled after Trump refused to take part in the virtual event proposed by the organisers after his Covid-19 diagnosis.

The debate was the last time the two will meet before the election.