Warren Ellis's Vice column, "How to Shut Down Internets," looks at the phenomenon of Middle Eastern dictators shutting off their nation's Internet during moments of extremis. Here's the money graf:
There are two reasons why these shutdowns happen in this manner. The first is that these governments wish to black out activities like, say, indiscriminate slaughter. That much is obvious. The second is sometimes not so obvious. These governments intend to turn the internet back on. Deep down, they believe they will be in their seats the next month and have the power to turn it back on. They believe they will win. It is the arrogance of power: they take their future for granted, and need only hide from the world the corpses it will be built on.
For me, this raises a couple of much more interesting questions:
1. Why would a basket-case dictator even allow his citizenry to access the Internet in the first place? (A: Because the national economy can't function without it)
2. Why not shut down the Internet the instant trouble breaks out? (A: Because it would be immensely unpopular, even among your sympathizers; also, see 1.)
Update: Bruce Schneier adds: "The reason is that the Internet is a valuable tool for social control. Dictators can use the Internet for surveillance and propaganda as well as censorship, and they only resort to extreme censorship when the value of that outweighs the value of doing all three in some sort of totalitarian balance."