The final presidential debate between Donald Trump and Joe Biden was held in Nashville, Tennessee.

Originally, plexiglass screens had been installed to separate the candidates but they were removed before the debate with the agreement of both campaigns.

It was the only thing the two sides would agree on throughout the night.

1. The Moderator 

The first presidential debate was moderated by Chris Wallace of Fox News and he struggled to keep proceedings under control amid constant interruptions, time overruns, insults and name-calling.

Last night's debate was a far calmer, more civil affair and much of that was down to the moderator Kristen Welker of NBC News. She moved candidates along and cut them off when they ran overtime.

"The goal is to hear each other and have the American people hear every word you say," she said at the start of the debate.

Chris Wallace praised her performance. "I'm jealous, I would have liked to have been able to moderate that debate and to get a real exchange of views instead of hundreds of interruptions," he said.

2. The Mute Button

There were so many interruptions during the first debate, organisers said they would mute microphones for this showdown to ensure candidates could make their points without being shouted down.

The decision generated a lot of headlines in the run-up to the debate but in the end the most interesting thing about the mute button is that it wasn't really needed. Donald Trump and Joe Biden kept interruptions to a minimum.

The US president clearly learned from his mistakes of the first debate when his aggressive tactics led to a fall in the opinion polls.

3. Hunter Biden

It was always expected that Donald Trump would attack his opponent by going after his son, Hunter Biden, who he has repeatedly accused of engaging in corrupt business deals with Russia, China and Ukraine.

The US president said some of Joe Biden's family members had been like vacuum cleaners, sucking up money and using Mr Biden's position as vice president to make themselves rich.

Joe Biden used his favourite catch-phrase to dismiss the allegations about his son as "malarkey" and went on the attack, accusing Donald Trump of being the one who is guilty of taking money from Russia and China.

4. The Talk

On the issue of racism, the moderator Kristen Welker asked the candidates about "the talk" that people across America are forced to have with their children, warning them that they may be targeted by police for no reason other than the colour of their skin.

Joe Biden spoke about his work with African-American communities and said there was institutional racism in the US.

Donald Trump highlighted what he has done for the African-American community, pointing to criminal justice reform and funding for historically Black colleges.

He also attacked Joe Biden's controversial 1994 Crime Bill, which critics say led to the jailing of thousands of Black people.

Mr Biden admitted that the drug sentencing element of the bill was a mistake and that he has been trying to change it.

5. Abraham Lincoln

Donald Trump has repeatedly claimed that he has done more for the African-American community than any president since Abraham Lincoln.

Joe Biden made fun of this when attacking his opponent's record on race, saying Donald Trump had a dog whistle like a fog horn.

"Abraham Lincoln here is one of the most racist presidents we've had in modern history... He pours fuel on every single racist fire," he said.

Donald Trump fired back, saying he never said he was Abraham Lincoln but rather he was comparing their records.

"I'm the least racist person in this room," he said.

6. Hitler 

There is an old rule in debating that as soon as you compare your opponent to Hitler you have lost.

Joe Biden didn't describe Donald Trump as Hitler last night but he did use the comparison when referring to the leader of North Korea, Kim Jong-un.

"Having a good relationship with leaders of other countries is a good thing," Mr Trump said.

"He's talked about his good buddy, who's a thug," Mr Biden replied.

"We had a good relationship with Hitler before he invaded the rest of Europe. C'mon man," he added.

7. The non-politician 

Although Donald Trump has been president for the last four years, he repeatedly portrays himself as the outsider: the newcomer, non-politician who is going to shake things up in Washington and "drain the swamp".

We saw a continuation of that last night with Mr Trump frequently attacking Joe Biden's 47-year political career, accusing him of achieving nothing.

"You are all talk and no action," he said.

When Donald Trump was attacking Hunter Biden, Joe Biden used his prepared response saying that it shouldn't be about the candidates' families but about American families who are struggling.

"What a typical politician answer," Mr Trump replied, "I'm not a typical politician."

8. Oil

He may claim to be a non-politician, but Donald Trump knows where the votes are.

During the section of the debate on climate change, Joe Biden said if he is elected, he would move the US away from oil.

"Oh. There's a big statement," Mr Trump replied in surprise.

"Will you remember that, Texas? Will you remember that, Pennsylvania? Will you remember that, Oklahoma?" the US president said.

9. Time Check 

Towards the end of the debate, the moderator said "we're running out of time". 

Joe Biden then took a long look at his wrist watch. 

"Big deal", I hear you say, but it did evoke memories of a 1992 town hall debate between Bill Clinton, Ross Perot and George HW Bush.

Mr Bush checked his watch while Bill Clinton answered a question from an audience member. He was widely criticised amid claims he was bored by the voter's concerns or perhaps was under pressure and wanted the debate to end.

Maybe Joe Biden wasn't checking the time at all and was instead looking at the date. 

It is, after all, only 11 days to election day.

The debate will be repeated on the RTÉ News channel at 9am

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