The book that I wrote is called Dark Money, and it's about secret spending that is very hard to follow. [George] Soros's whole thing is about government transparency, so he spends very much in the open, and the same with [Tom] Steyer.

Donald Trump actually is a pretty big-government conservative. He doesn't see eye-to-eye with them [the Kochs] on trade.

In fact, Charles Koch tried to get [Mike] Pence to run for the White House in 2012.

They [the Kochs] want free trade and cheap labour. They own the second-largest private company in America, which is a huge multinational corporation. So they are on a different wavelength.

[Donald] Trump comes along and is singing a different song. He says, "I don't need your money; I'm rich enough on my own to run." And he says, "I think we need these programs." And, lo and behold, a lot of Republican voters liked what he said.

Barack Obama was elected President in 2008 and re-elected in 2012. The natural thing would be to suggest money on the right [wing] doesn't really matter that much. The first thing you have to know is that the presidential elections are the ones where it's most difficult for money to hold sway, in that they're the most public elections.

It was our view of the worst that could befall our people if they were taken captive. So, what was fascinating to me was that somehow it appears the techniques that we have feared most in the world would be used on our people, we are using on people in our custody.