In the post-debate spin room after the third Demcoratic debate, CBS News' Ed O'Keefe pressed Julián Castro on his line of attack against Joe Biden, perhaps the most memorable exchange of the night. Castro accused Biden of contradicting himself and wondered whether the former vice president's memory was failing him in what appeared to many to be an attack on Biden's age.
"Are you forgetting what you said two minutes ago? Are you forgetting already what you said just two minutes ago? I mean, 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 to Biden. "You're forgetting that."
On stage, Pete Buttigieg scolded Castro, saying, "This reminds everybody of what they cannot stand about Washington.
"That's called an election, Pete," Castro retorted.
O'Keefe pointed out that some of Castro's rivals' campaigns called his attack "disqualifying" and a "low blow."
"This wasn't about personalities. This was about a difference in health care policy," Castro argued. He explained that the debate in Detroit, Kamala Harris had said Biden's health care plan would leave 10 million people uncovered.
Castro asserted that media fact checkers agreed. "This was a conversation about why he's denying saying that you would have to 'buy in,"' Castro said. "If you lose your job, you would automatically 'buy in"' and "not everybody can buy into a plan," he told O'Keefe.
Castro reiterated that his approach would cover more people because they'd be automatically covered, and he said Biden's approach — "buying in" — means the former vice president's plan would leave 10 million people uncovered because many would not be able to afford to buy insurance. That's why, Castro said, it was "really important for me to zero in on that."
So, as he remembered it, "When [Biden] denied saying 'buy in,' I said, 'Didn't you just say "buy in" — like two minutes ago?"'
O'Keefe pulled up the transcript of the debate on his phone and read it to Castro: "He does say here that anyone who can't afford it gets automatically enrolled in the Medicare-type option we have." Then later on, O'Keefe noted, Biden said that if you lose your insurance from your employer you could automatically "buy into this."
"That's right – he said you would have to buy into it," Castro said. "I said, 'You just said you would have to buy into it, and because of that, it leaves people uncovered.' He said, 'I didn't say buy in.' I said, 'Yes, you did say "buy in," you just said that, did you forget you said that?' So this was a conversation about why he's saying he's denying saying you would have to buy in. That is factual, that is not something that wasn't grounded in fact."
When O'Keefe noted that other candidates who'd attacked Biden -- Eric Swalwell and Kirsten Gillibrand are two examples -- are no longer running, Castro remarked, "That's what a debate is for."
"So I would say to Democrats out there, when we go up against Donald Trump in October of 2020 on the debate stage, look, you'd better come ready to prove your point," Castro said. "I'm always ready to prove my point. I did it in a respectful way, I did it about healthcare policy, but I proved my point. And if I'm on that debate stage against Donald Trump, I'm going to get the better of Donald Trump, too. "