Underestimate That âSenileâ Biden Guy At Your Peril In a Democratic presidential debate in September 2019, Julian Castro thought he heard Joe Biden say something that contradicted himself, and he pounced on the opportunity to suggest that Biden was over the hill. "Are you forgetting what you said two minutes ago?" he demanded. "Are you forgetting already what you said just two minutes ago?" Propelled by this moment of triumph, Castro went on to become a member of the board of directors of a Washington think tank. His humiliated opponent was never heard from again. As it turned out, it was Castro who was confused about what Biden had said. If the 2020 campaign proved anything, it's that underestimating Biden is dangerous. But Republicans persist in depicting him as a decrepit specimen who is wholly inadequate to his presidential responsibilities.