David Gergen: “This is one of the threshold questions that when you run for high public office, you have to face.”

We're entering some kind of the most dangerous days of Donald Trump's presidency. He is erratic.

I think the turning point that came were the midterm elections. The fever broke with those midterm elections. And what we've seen since then is a steady decline in Trump's credibility and in his position with the American people, and a…

I think it's going to take something usually unexpected or a dramatic change in his health or a prison sentence to stop him.

I think what we're seeing is the Aguero story just underscores how vital it is that we have a National Commission to investigate what happened on January 6th, and we cleared the air on it.