Many Americans were worried about Joe Biden's age and fitness for office before Thursday night's debate. Unfortunately, the debate didn't ease those concerns. Biden struggled throughout, often appearing flat, rambling, and unclear.

Midway through the debate, the Biden campaign revealed that the president had a cold, explaining his raspy voice. While this might have been true, it seemed like an excuse for his performance.

For much of the 90-minute debate, Biden was on the defensive. Some of his early responses were incoherent. He even ended one answer with a confusing statement, "We finally beat Medicare," referring to the government healthcare program for the elderly.

Biden’s campaign had planned to be aggressive against Donald Trump, but instead found themselves on the defensive. Top campaign surrogates were cornered by reporters, fielding questions about whether Biden, 81, should be replaced at the top of the ticket due to concerns about his fitness for office.

David Plouffe, a Democratic strategist who managed Barack Obama's 2008 campaign, described the situation as "a Defcon 1 moment," the highest level of a nuclear threat. He noted that while Biden and Trump are less than four years apart in age, they seemed decades apart in their debate performances.

Andrew Yang, who competed against Biden in the 2020 Democratic primary, suggested on social media that Biden should "step aside and let the DNC choose another nominee," using the hashtag #swapJoeout.

Despite these calls, it's unlikely Biden will be replaced as the Democratic nominee. As the incumbent president, with only a few months left before the election, changing nominees now could create chaos and harm the party’s chances in November.

Amanda Litman, who works to recruit young Democratic candidates, told the BBC the debate highlighted the need to end the "gerontocracy" after defeating Trump and saving democracy.

David Axelrod, another former Obama advisor, said on CNN, "I think his job just became a little bit harder."

In the debate spin room, Biden’s campaign surrogates faced a barrage of questions about his performance. Despite their efforts, they couldn't shift the focus of the conversation. Congressman Robert Garcia of California criticized Trump, saying he "lied, and lied, and lied again."

Trump did make misleading statements, such as falsely claiming that Democratic-controlled states wanted to allow abortion "after birth" and accusing Biden of encouraging Russian President Vladimir Putin to attack Ukraine, despite Biden’s administration strongly supporting Ukraine.

The Biden campaign echoed these points, branding Trump as a liar and a criminal in their post-debate statements. Vice-President Kamala Harris also criticized Trump, saying he "lied over and over and over again."

At a post-debate watch party, Biden told supporters, "They're going to be fact-checking all the things he said. I can't think of one thing he said that was true."

He continued, "Look, we're going to beat this guy, we need to beat this. I need you, in order to beat him. You're the people I'm running for."

Following the debate, Trump’s potential running mates and top campaign staff declared victory for their leader. Meanwhile, Democratic figures like Governor Gavin Newsom, Congressman Garcia, and Senator Raphael Warnock made brief appearances, repeatedly answering questions about Biden’s performance.

Former Democratic Senator Claire McCaskill summarized the challenge for Biden’s surrogates, saying, "When you’re a surrogate you have to focus on the positives."

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