I have spoken with people who have known Trump for decades and who say he has changed. He exhibits less self-awareness, these longtime acquaintances say, and less capacity for sustained focus. Indeed, it is instructive to compare television interviews of Trump recorded years ago with those conducted now. To this layman’s eyes and ears, there seems to have been deterioration.

I am not professionally qualified to assess the president’s mental health; psychiatrists and psychologists who have the proper credentials and experience to do so are silenced by ethical rules. The stakes are so high, however, that the officials who work alongside Trump and observe him closely bear a tremendous responsibility. There is a huge difference between sounding as unhinged as North Korea’s Kim Jong Un and actually being that unstable.