It was stupid to go in front of a lib editorial board, let alone they had a camera. I forget the politician but a few years ago he stopped doing newspaper editorial board interviews because of the “trap” they are.
I don’t think that was stupid. If, as the campaign said later, he did so on 4 hours sleep, that was probably a bad idea. If he offered to answer questions about foreign policy, and decided not to learn foreign policy beforehand, that was probably a mistake.