Sometimes that irrational commitment to principle is what society needs to survive. Whenever you talk about radicalism, whenever you talk about activism, whenever you talk about progressive activity, that sort of moves the measure of liberty in human society forward, makes us all enjoy a better standard of liberty, it typically starts out criminal. It typically starts out a little bit shaky, and rather radical. And that's irrational to put yourself up to do that.

You simply have to eventually fall under suspicion from somebody even by a wrong call. And then they can use this system to go back in time and scrutinize every decision you've ever made, every friend you've ever discussed something with. And attack you on that basis to sort to derive suspicion from an innocent life and paint anyone in the context of a wrongdoer.

All the governments just want to have more power when it comes to economic espionage, diplomatic manipulation and political influence.

Are our competitors - for example, China, which is a deeply authoritarian nation - becoming more authoritarian or more liberal over time?

Sometimes that irrational commitment to principle is what society needs to survive. Whenever you talk about radicalism, whenever you talk about activism, whenever you talk about progressive activity, that sort of moves the measure of liberty in human society forward, makes us all enjoy a better standard of liberty, it typically starts out criminal. It typically starts out a little bit shaky, and rather radical. And that's irrational to put yourself up to do that.

A child born today will grow up with no conception of privacy at all. They'll never know what it means to have a private moment to themselves an unrecorded, unanalysed thought. And that's a problem because privacy matters, privacy is what allows us to determine who we are and who we want to be.

In the United States, there hasn't been much legislative change on the surveillance issue, although there are some tepid proposals.