Scott Adams has a post up on the possible reasons for the attack on Libya. He reckons that:

“[T]he military action in Libya is the first phase of war with Iran. It sends a signal to the young people in Iran that if they organize a popular uprising against their own regime, they will get military support of the same sort they are seeing in Libya.” 

One possible flaw in this idea is that the Iranian youth did that two years ago. And we didn’t intervene. And lots of people thought it was the right decision.