Military commanders do not want to be tried for war crimes, even if those crimes are committed online.

Dictators aren't stupid, or regimes could be toppled easily by young people mobilizing on Facebook.

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.

As Barbara Streisand discovered, adopting a militaristic posture against a tech-savvy mob of civil libertarians is not going to be of much help: Many of them run their own servers and blogs - and have thousands of friends on their social networks - so overzealous attempts to silence them only lead to wider dissemination of sensitive information.

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.

Diplomacy is, perhaps, one element of the U.S. government that should not be subject to the demands of 'open government'; whenever it works, it is usually because it is done behind closed doors. But this may be increasingly hard to achieve in the age of Twittering bureaucrats.

As befits Silicon Valley, 'big data' is mostly big hype, but there is one possibility with genuine potential: that it might one day bring loans - and credit histories - to millions of people who currently lack access to them.