After what was generally judged to be a disastrous performance by President Joe Biden in his first televised debate with Donald Trump in the 2024 cycle, national Democrats went into panic mode on Thursday night as only Democrats can do. Democratic strategist after Democratic strategist told reporters that America’s last hope was a brokered Democratic National Convention or, as one put it, for Biden to die. Texas Democrats, meanwhile, were pretty quiet, at least in public, where they mostly stuck to tweeting preapproved memes. With one exception: former San Antonio mayor and secretary of housing and urban development Julián Castro. 

“Tonight was completely predictable,” Castro said. He argued that it was a man-made disaster, rather than an act of God. “Biden had a very low bar going into the debate and failed to clear even that,” he went on. “He seemed unprepared, lost, and not strong enough to parry effectively with Trump, who lies constantly.” During the debate, Castro reposted the political analyst Dave Wasserman’s suggestion that Biden’s decision to run again had been a grave mistake.

Castro felt free to speak out likely because he no longer holds public office. But he doesn’t hold public office in part, perhaps, because he spoke out on this issue once before. In 2019, Castro ran in the Democratic primary for president. By September his campaign was teetering and needed a miracle. Biden, the front-runner, looked unsteady, and many thought he was coasting on name recognition. Castro elected to give him a body check. At a debate that month, he thought he caught Biden misstating aspects of his health care plan, and he pounced. “Are you forgetting already what you said just two minutes ago?” he said. There was audible shock in the audience. “I can’t believe that you said two minutes ago that they had to buy in, and now you’re saying they don’t have to buy in,” Castro said. Then: “You’re forgetting that?”

That was one of several times in the debate that Castro laid into Biden, but it gained attention because it violated what had become a quiet taboo against raising the issue of Biden’s age and mental competence. The former vice president had become Democrats’ “Uncle Joe,” and for many watching the debate, Castro’s dig was uncomfortable to watch. Castro would later say he had meant not to question Biden’s mental competence but to try to catch a fellow candidate in a contradiction. 

Whether on purpose or inadvertently, the San Antonian was saying what a lot of the audience was thinking. He was arguably right, but he spoke in a sharp-elbowed, clumsy way that made many in his party think he wasn’t ready for prime time. Biden wasn’t the paper tiger some in the primary thought he was: he went on to become the consensus candidate for Democrats when none of the littler candidates—the Buttigieges, Klobuchars, and O’Rourkes—could break through. Castro’s campaign was misconceived from the get-go. He tried to outflank his rivals from the left but consistently stumbled trying to do so.

The bigger problem is that he was right too early. Biden’s public presence in 2019 was woollier than it was when he was vice president, but he was still capable of performing in high-pressure scenarios. Even as he was elected, he reportedly hinted that he would serve only one term. His advisers could handle most of the load, and Democratic voters could choose to overlook his occasional misfires. It’s only now, in 2024, that Biden’s age has become an existential problem for the republic.

Castro’s line of attack seemed to rebound on him even after the race was over. Many of Biden’s former rivals in the race reconciled and found gigs in the new administration—among them Vice President Kamala Harris. Castro, who endorsed Massachusetts senator Elizabeth Warren, didn’t get tapped by the new administration, and his career in public life sputtered. He took a contract with MSNBC. (Both Julián and his twin brother, Joaquin, a congressman from San Antonio, have had an uneasy relationship with the Biden administration. Joaquin, who serves on the House Foreign Affairs committee, has been increasingly vocal about the human cost of the Israel-Hamas war, which the administration has helped prolong.)

In 2023 the New York Times interviewed Julián about Biden’s candidacy. By this time, the taboo against questioning his fitness for office was much stronger. Castro spoke at length about his fear of Trump’s second term and his desire that a Democratic candidate win—but after some prodding he suggested that Biden’s age was a real problem. “He needs to do everything he can,” Castro said, “to show age is just a number,” to show leadership and “be energetic about it.” Biden’s team, he said, was “doing some of that, but I don’t feel like they’re doing enough. Sometimes I feel like the team does not recognize how much that idea has permeated regular people.”

In the interview, Castro suggested it would be healthier for Democrats to discuss these issues openly than to try to maintain rigid silence. When Castro tweeted that Biden’s debate flop was “predictable,” it seemed to voice frustration about what Democrats, collectively, decided not to understand.