This was maybe the worst presidential debate in American history.

If this was supposed to be a boxing match, it instead turned into Trump jumping on the ropes, refusing to come down, the referee trying to coax him off and Biden standing in the middle of the ring with his gloves on and a confused look on his face.

Trump doesn't play by anyone's rules, even those he's agreed to beforehand. He's prided himself on that. But even by his standards, what Trump did Tuesday night crossed many lines.

He's president. More than 200,000 Americans are dead from the coronavirus pandemic. And instead of a serious debate about the direction of the country, Trump sent it off the rails.

Most charitably, both former Republican Pennsylvania Sen. Rick Santorum and former Republican New Jersey Gov. Chris Christie, who helped Trump prep for the debate, said he was "too hot."

"I think the president overplayed his hand tonight," Santorum said on CNN.

Here are six takeaways from the first Trump-Biden debate.

1. Even for Trump, he went too far

For part of the debate, Trump looked like he was controlling the stage. He interrupted constantly and tried to distract, deflect and interject. That's fairly typical Trump behavior, but a few things in particular were egregious.

When Biden, for example, was talking about his late son Beau's military service, Trump went in on Biden's other son, Hunter, and brought up his past cocaine use. It backfired.

Biden, looking directly to the camera, turned something he rarely talks about into a positive, sympathetic moment.

"My son, like a lot of people you know at home, he had a drug problem," Biden said. "He's overtaken it. He's fixed it. He's worked on it. And I'm proud of him."

Later, when Trump was asked to denounce white supremacists and militia groups — and specifically the far-right extremist group Proud Boys — he instead said this: "Proud Boys, stand back and stand by." And then he denounced left-wing groups. (Proud Boys is now using Trump's words as part of a new logo.)

What's more, Trump would not urge his followers to remain peaceful as votes are counted, including if there are delays in reporting the results.

"I'm urging my supporters to go into the polls and watch very carefully because that's what has to happen," Trump said, adding, "If it's a fair election, I am 100% on board. If I see tens of thousands of ballots being manipulated, I can't go along with that."

2. Trump likely did nothing to expand beyond his base

Trump's base will probably love his performance. But coming into the debate, Trump was behind in the polls. That's no secret.

He needed to try to win back suburban and independent voters, both of whom he won in 2016 and who have largely abandoned him this cycle.

So who was this performance for exactly?

Trump repeated his "law and order" appeal to white, suburban voters and tried to force Biden to repeat the words. But Biden didn't take the bait and pivoted, calling for "law and order with justice where people are treated fairly."

And Biden said this about Trump and the nature of his appeal.

"He wouldn't know a suburb unless he took a wrong turn," Biden said. "I was raised in the suburbs. This is not 1950. All these dog whistles and racism don't work anymore. Suburbs are by and large integrated."

3. Biden missed opportunities

This was not Biden's cleanest debate. He was not crisp, was often flummoxed — as was moderator Chris Wallace of Fox News — by Trump's antics.

"Will you shut up, man?" said Biden while trying to make a point. He also called Trump a "clown" more than once.

Biden missed some opportunities. For example, when Trump was talking about the role of masks in preventing the spread of the coronavirus, Biden could have interjected more forcefully to talk about Trump's largely maskless rallies. When Trump claimed his rallies caused no harm, Biden could have pointed out the spike in coronavirus cases after Trump's Tulsa, Okla., rally.

The former vice president had some stumbles and some moments that weren't great for him, like not answering if he would add justices to the Supreme Court — "pack the court" — if Judge Amy Coney Barrett, Trump's nominee to succeed Ruth Bader Ginsburg, is confirmed.

That was likely overshadowed by Trump's demeanor, but for the next debate — if there is one — Biden's team will need to try to sharpen him up.

4. Trump tried to tie Biden to the far left, but it didn't work

Trump tried his darndest to paint Biden as a socialist, or at least beholden to the "radical left." But on issue after issue — "Medicare for All," defunding the police, the Green New Deal — Biden disavowed policies the Trump campaign has tried to lasso to him.

Biden just restated his positions, and they all line up with the middle of the electorate, far more than Trump's policy positions do.

That might have harmed Biden with the progressive left, particularly when it comes to the Green New Deal, if Trump hadn't gone quite so Trump.

5. Trump's response on his handling of COVID-19 was more of the same

More than 200,000 Americans have died from COVID-19, and coronavirus cases are spiking again in some parts of the country.

And yet Trump's tactic when defending himself on his management of the pandemic was to insult Biden's smarts.

"He panicked or just looked at the stock market, one of the two, because guess what?" Biden said. "A lot of people died and a lot more are going to die unless he gets a lot smarter a lot quicker."

Trump's response?

"Did you use the word 'smart?' " Trump asked rhetorically, adding, "You graduated either the lowest or almost the lowest in your class. Don't ever use the word 'smart' with me."

Trump said he disagreed with his own experts on a vaccine timeline, insisting it would soon be widely available. But making rosy assertions to the public is exactly what got him in trouble after Bob Woodward's latest book, Rage, revealed that Trump privately knew the virus was worse than he let on publicly.

He tried to claim Biden would have made the pandemic worse. "Two million would be dead now," he said.

But Trump is president, and, on average, a majority of Americans say they disapprove of the job he's doing handling the coronavirus.

6. Good luck to the next moderator

Before the debate, Wallace said his goal was to be "invisible."

By the end, he might have wished he was. The role was no easy task, and the next presidential debate, Oct. 15, is set to be moderated by the far more mild-mannered Steve Scully of C-SPAN.

After the first presidential debate of the 2004 election, Internet conspiracies abounded about a mysterious bulge in the back of President George W. Bush's jacket. Some believed, unfoundedly, that there was a communications system rigged up by White House advisers to coach him.

Bush dismissed that, cracking wise.

"I guess the assumption was that if I were straying off course they would ... kind of like a hunting dog, they would punch a buzzer, and I would jerk back into place," Bush said afterward.

Maybe something to look into.

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