If Donald Trump had faced a halfway plausible and competent adversary, tonight’s debate would have marked the death of the former president’s hopes for returning to the White House. Simply put, Trump gave the second-worst debate performance of any major candidate for president, but… He repeatedly made outrageous and offensive lies, such as his claim that overturning Roe v. Wade was “something everybody wanted.” (In point of fact, polls show 65 percent of Americans opposed the Supreme Court’s decision to end the constitutional right to abortion.)

Despite repeated questions on this point from moderator Dana Bash, Trump refused to say he would accept the results of the election if he lost (which only served to remind Americans that he had refused to accept the results of the 2020 election and instead had egged on a mob to attack to the Capitol). He angrily refused to address many of the questions he was asked directly and instead kept harping on his pet issue that undocumented migrants were destroying America. Even as most Americans have started to oppose Israel’s onslaught in Gaza, Trump made the horrifying promise that he would let Israel “finish the job.” He made gaffes like referring to migrants taking away “Black jobs.” And, as fact-checkers such as CNN’s Daniel Dale documented, Trump repeatedly lied about many things great and small. As one example, Dale notes:

Trump’s claim that some Dem states allow people to execute babies after birth is fiction. No state allows this. He’s said the state he’s talking about is New York, which doesn’t allow this, though false social media memes have said it does.

Unfortunately, Dale’s fact-checking was confined to Twitter and the CNN webpage, as well as post-debate commentary. On stage, no one challenged Trump’s absurdities and fictions. Moderators Jake Tapper and Dana Bash let them go unchallenged. Joe Biden did note that Trump was lying, but Biden’s rebuttals were so fuzzy and incoherent that they lacked any ability to convince.

Biden repeatedly stumbled through questions as if he were trying to dredge up a half-remembered script. He often rambled into strange and hard-to-understand directions. In a stomach-turning moment, he derailed a discussion about one of his strongest issues (abortion) by bringing up immigration, the very topic Trump wants the election to be about. It was a completely unforced error on Biden’s part.

At one point Biden gave a rambling and hard-to-follow talk about taxes that ended with the bizarre statement, “We finally beat Medicare.” Trump naturally jumped on this gaffe. Biden likely was trying to say, “We finally beat the rising cost of Medicare,” or some similar, and accurate, statement. But he was too lost in his own words to make the case.

As the writer Eyal Press noted, “An alert, articulate Democrat would be hammering Trump. Biden is hanging on the ropes.”

Months of debates over Biden’s age should now be over. He’s clearly not up to the job of fending off the disaster of a Trump presidency.

The question now is: Do Democrats have a Plan B?

The only plausible scenario is for the party’s ranking members of Congress and party elders such as Barack Obama, Bill Clinton, and Hillary Clinton to converge on the White House to tell Biden to withdraw his nomination for the good of the party and the country (not to say the world). Kamala Harris would then become the party’s nominee and she could select a vice-presidential pick from among the party’s wide range of talent.

Those who still harbor fantasies of a brokered convention clearly haven’t been paying attention. The Democratic National Committee just moved the presidential nomination roll call up to August 7 so that Biden can get on the ballot in Ohio. Biden already has a total lock on pledged delegates, and even if he could be persuaded to release them, there is no process for adjudicating a successor.