Surveillance cameras might reduce crime - even though the evidence here is mixed - but no studies show that they result in greater happiness of everyone involved.

When someone at the State Department proclaims Facebook to be the most organic tool for promoting democracy the world has ever seen - that's a direct quote - it may help in the short run by getting more people onto Facebook by making it more popular with dissidents.

Personalization can be very useful in some contexts but very harmful in others. Searching for pizza online, it's probably OK to keep showing the same pizza shop as your No. 1 choice. I don't see any big political consequences out of that.

This is the real tragedy of America's 'Internet freedom agenda': It's going to be the dissidents in China and Iran who will pay for the hypocrisy that drove it from the very beginning.

To fully absorb the lessons of the Internet, urge the Internet-centrists, we need to reshape our political and social institutions in its image.

The Egyptian experience suggests that social media can greatly accelerate the death of already dying authoritarian regimes.

Mobile phones are one of the most insecure devices that were ever available, so they're very easy to trace; they're very easy to tap.