This is kind of basic, but I'm struck by how different our intervention in Libya is from Afghanistan. In Libya, you can see obvious and measurable progress -- the rebels have slowly but steadily gained territory, defending their capitol, taking the crossroads town, taking the oil towns, and now they're at the capitol. Gadhafi's officials have defected as the rebels won battles. In Afghanistan, everything is murky and there's no visible signs of progress. And that's with 6 months of helping from the air in Libya and nearly 10 years of US ground troops in Afghanistan.
Of course, there's still plenty of challenges ahead in Libya. From deposing Gadhafi to constituting a government to holding fair elections to not falling back into a civil war of some sort, the really difficult parts are yet to come. But so far, so good.