The president sets the tone. He creates the atmosphere, and that can be enlightened, progressive, or it can be intimidating, depending on what the president's agenda is. I think the other dimension of this that I worry about is impacts overseas with friends and allies, many of whom are very, very concerned about America's position in the world and whether or not it's going to continue its leadership, which has been the prevalent condition since World War II.

We had a general awareness, for example, of Russian use of social media - Facebook ads, use of Twitter, fake news implants - we had a general understanding of that. But now, as time has elapsed and time has gone on, I've certainly learned a lot more about the depth and breadth of what the Russians were about.

I think, as a professional courtesy, when the president asks you to dinner, you go.

When I visited North Korea in November 2014, is that Kim Jong-un is not merely the head of state of the DPRK - the Democratic People's Republic of Korea, North Korea - he's also their deity. So, when you insult him as the head of state, you're also insulting the deity, which of course the regime plays to a fare-thee-well to the domestic audience there.

We're talking about nuclear war with North Korea. We're talking about Russia. Does it feel like the world has shifted? Are we all just in Donald Trump's reality show now?

The Russians succeeded, I believe, beyond their wildest expectations. Their first objective in the election was to sow discontent, discord, and disruption in our political life, and they have succeeded to a fare-thee-well. They have accelerated, amplified the polarization and the divisiveness in this country and they've undermined our democratic system. They wanted to create doubt in the minds of the public about our government and about our system; and they succeeded to a fare-thee-well. They've been emboldened and they will continue to do this.

The president sets the tone. He creates the atmosphere, and that can be enlightened, progressive, or it can be intimidating, depending on what the president's agenda is. I think the other dimension of this that I worry about is impacts overseas with friends and allies, many of whom are very, very concerned about America's position in the world and whether or not it's going to continue its leadership, which has been the prevalent condition since World War II.