No one would argue that it's in the United States' interest to have independent knowledge of the plans and intentions of foreign countries. But we need to think about where to draw the line on these kind of operations so we're not always attacking our allies, the people we trust, the people we need to rely on, and to have them in turn rely on us.

Radicals are not going to disappear. They're going to go underground. They're going to be hardened. And they're not going to be exposed to contrary ideas made by educated people who can make real, convincing, and persuasive arguments to deradicalise these people.

I'm ultimately satisfied that we know a little bit more about how the world really works.

You can't come up against the world's most powerful intelligence agencies and not accept the risk.

I have been a systems engineer, systems administrator, a senior adviser for the Central Intelligence Agency, a solutions consultant and a telecommunications information systems officer.

Even if it were, you run into the same problem with international commerce: if you create a device that is famous for compromised security and it has an American back door, nobody is gonna buy it.

You are also asked to take an oath, and that's the oath of service. The oath of service is not to secrecy, but to the Constitution - to protect it against all enemies, foreign and domestic. That's the oath that I kept, that James Clapper and former NSA director Keith Alexander did not. You raise your hand and you take the oath in your class when you are on board. All government officials are made to do it who work for the intelligence agencies - at least, that's where I took the oath.