People are starting to understand that the devices we carry with us reveal our location, who we're talking to, and all kinds of other information.

That's a question you'd have to present to people in the White House.

One of the most frightening things, I think, is the capacity for retroactive searching, so you can go back in time and trace who someone is in contact with and where they've been.

One of the things that I think is true is that encryption actually is able to secure our communications, that every individual can use encryption, and that it's accessible and in many cases free.

We don't stand here alone, it's possible through the great organisations that support us. The disclosures that Edward Snowden revealed aren't only a threat to privacy but to democracy, when the most important decisions made affect all of us. Thank you to Edward Snowden. I share this with Glenn Greenwald and other journalists who are exposing truth.

So my first experience was that I had to do a reboot of my expectations. Like fantastic, great, he's young and charismatic and I was like wow, this is so disorienting, I have to reboot. In retrospect, I can see that it's really powerful that somebody [Snowden] so smart, so young, and with so much to lose risked so much.

In terms of sources coming forward, I really reject this idea of talking about one, two, three sources. There are many sources that have informed the reporting we've done and I think that Americans owe them a debt of gratitude for taking the risk they do.