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.

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.

One of the lessons we've learned from the last 25 years of terrorism is that groups that have safe havens are able to develop external attack capabilities in a way that groups that don't have safe havens are not. So we need to find a way to squeeze them significantly in their safe haven. Taking away territory that really matters to them is really, really important because it prevents them from focusing on external attacks.

[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 far as Paris goes, we don't know for sure yet how these guys communicate among themselves and how they communicated back to the ISIS leadership in Iraq and Syria, but I'm fairly confident we're going to learn they used these encrypted communication applications that have commercial encryption and are extremely difficult for companies to break - and which the companies have made the decision not to produce a key for.

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.

Look at it from [Vladimir] Putin's perspective, right. He's a trained intelligence officer, worked for the KGB, very talented, manipulated people much smarter than Donald Trump. He played this perfectly, right. He saw that Donald Trump wanted to be complimented.