Even if you think the reason we're intervening is for selfish reasons, that doesn't mean we ought not do it. Furthermore, "we should be intervening in countries Y and Z as well" is not an argument against intervening in country X. In this case, Obama was carefully tiptoeing around this issue and quietly reassuring Gaddafi for the first few days, waiting to see which way the wind was blowing. Now that it's apparent that not only the American public but most of the United Nations too were supporting this action, the U.S. Government has smelled blood in the water and is preparing to pounce.
Again - don't appeal to motivations (i.e. "they're only helping because they want oil/hookers/whatever), but explain to me why I shouldn't be behind this action, which is itself not an actual invasion ala Iraqistan? The US supports regional dictators the world over, but Realpolitik demands that they do this for pragmatic reasons. I'm disgusted by it, yes, but that does not imply that I shouldn't be supportive when the goals of the US Gov and the morally acceptable intervention happen to coincide.
