I did the first study because I had been exposed to something that I took to be important and interesting - this thought reform process - in the military.

People with what we call mental illness can indeed serve well, and people who have no discernible mental illness - and that may be true of Trump - may not be able to serve, may be quite unfit. So it isn't always the question of a psychiatric diagnosis. It's really a question of what psychological and other traits render one unfit or dangerous.

There are people who believe that there should be a standard psychiatric examination for every presidential candidate and for every president. But these are difficult issues because they can't ever be entirely psychiatric. They're inevitably political as well. I personally believe that ultimately ridding the country of a dangerous president or one who's unfit is ultimately a political matter, but that psychological professionals can contribute in valuable ways to that decision.

We have a duty to warn on an individual basis if we are treating someone who may be dangerous to herself or to others - a duty to warn people who are in danger from that person. We feel it's our duty to warn the country about the danger of this president. If we think we have learned something about Donald Trump and his psychology that is dangerous to the country, yes, we have an obligation to say so.

It may sound terrible, but I often say that the military saved me from a conventional life in the United States and I've never really thanked them for it, because I haven't exactly been pro-military in my work.

With the nuclear threat we know that if sufficient weapons are used, human civilization - all of humankind - could be extinguished literally by "nuclear winter." So we have to see ourselves as part of the ultimate human group, just as we have to do with global warming.

Yes, I've been very preoccupied with the survivor all through my work.