Yea, in hindsight it would have been better to just let him crack down on the population to keep stability in the region, but with the information we had at the time, most African and Arab neighbours agreed that helping the rebels with a no-fly zond would be better than not to, since the civil war was going to start anyway. You don't care about legality, but that is not the point. The point is that this was not unilateral, like Iraq, and even then military interventions can go terribly wrong.