Appearing on New Day, Castro was put on the spot after appearing to question Biden's mental capability and accusing him of not being able to remember what he said from moment to moment.
Berman began by asking Castro if he had any regrets about his skirmish with Biden which became the main topic of discussion after the debates, with Castro slapping that assertion aside.
"I wouldn't do it differently," Castro remarked. "That was not a personal attack. This was about a disagreement over what the vice president said regarding health care policy, and I'm glad, actually, that a lot of journalists overnight did the work of actually looking at the transcript."
"I do want to ask you about the differences in the plans and exactly what you were speaking about and exactly what Joe Biden said about his plan in just a moment," Berman persisted, "But back to what you said, because you said it wasn't personal. Not once, not twice, but three times, you asked him, 'are you forgetting what you said two minutes ago? Are you forgetting already?' you said, and then you said, 'you are forgetting that." Why did you keep saying that? "
"Number one, he couldn't hear me in the auditorium," Castro claimed. "If you look at what happened in the video. Secondly, look, that's a question that I would ask any opponent on-stage if I'm asking them in a debate. Because he had just denied what he said two minutes before. So I was asking him, 'are you forgetting what you said two minutes ago, because you just said it.' And in fact, when you look at the transcript of the video, that's what he said."
"Are you asking us to believe -- believe -- are you asking us to believe this morning that you weren't questioning Joe Biden's memory?" Berman pressed.
"Oh, I was questioning why he was saying that he hadn't said the words 'buy in,' which is significant to health care policy, when he had just said that two minutes ago," Castro answered.
"Are you questioning his memory? Are you questioning his memories -- do you have questions about Joe Biden's memory," the CNN host asked again.
"I was questioning -- look, this is the game that the media like to play," Castro shot back.
"It isn't a game, Mr. Secretary," Berman explained. "You said this three times and you are a very skillful politician who chooses your words very, very carefully."
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