The FBI is unique in that it straddles both law enforcement and counterintelligence.

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?

Trump is very skillful at identifying - even if he can't quite get it clear, or precisely describe it - but that's what he wants to do, is always have something to use against people, even if it's distorted.

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.

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.

Impeachment is our system's last resort for someone who treats himself or herself as above the law, the most relevant thing is whether this president, by his recent course of action, on top of his violations of the foreign corruption or emoluments clause, this president has shone that he cannot be trusted to remain within the law and our constitution's last resort for situations of that kind is to get the person out of office.