I worked with [Hillary Clinton] for four years very closely when she was secretary of state and I was at the CIA. I provided her - personally provided her some of the most sensitive information that the Central Intelligence Agency has.

ISIS went to school on how we were collecting intelligence on terrorist organizations by using telecommunications technologies. And when they learned that from the [Edward] Snowden disclosures, they were able to adapt to it and essentially go silent.

Donald Trump didn't even understand, right, that [Vladimir] Putin was playing him. So, in Putin's mind, I have no doubt that Putin thinks that he's an unwitting agent of the Russian Federation, although Putin would never say that.

From Mr. [Donald] Trump's perspective, right, he simply heard [Vladimir] Putin compliment him. He then responded by complimenting him. He never thought that he might be being played.

The one thing that struck me right off the bat was what Donald Trump said about Benghazi.There is this view out there that [Hillary Clinton] lied about what caused the attack, that she said it was the video.

Intelligence officers are supposed to put the facts on the table and really walk away from the policy discussion.

[Hillary Clinton] never misused [ information that the Central Intelligence Agency has]. She always protected it. I would trust her with the crown jewels of the United States government. And, more importantly, I would trust her with the future security of the country and the future security of my kids.

As the briefer, my job is to carry CIA`s best information and best analysis to the president of the United States and make sure he understands it.

Companies made these decisions about encryption when they were finding it very difficult to sell their products overseas because the [Edward] Snowden disclosures created the impression that the U.S. government was inside this hardware and software produced by them. They needed to do something to deal with the perception.

You have to have a military and intelligence approach to removing leadership that results in rapid frequent removals from the battlefield. It's got to be one, two a week, not just one or two every three or four months.