Gaddafi must go but who will make him go?

The West is facing a paradox. It wants Gaddafi to go without using the force required to make this possible. In a way the fear of civilian losses which could undermine the credibility of the whole venture is more than understandable. So is the need to operate within the narrow confines of a UN resolution which gives the whole operation the stamp of international legality. Still the more time passes, the more it seems that prudence will prolong the civil war and the suffering on the ground. Surely western intervention has this time round avoided a massacre by stopping Gaddafi from taking Benghazi. Those who oppose intervention should know that if they had their way, Gaddafi would have simply won. But are we happy with simply keeping Gaddafi out of Benghazi (while still endangering civilian lives in Misrata)? And since negotiations with a war criminal are impossible and there is no other option but removing him and his family from power, what alternatives exist to either arming the rebels to enable them to win or to engage in a full scale war with one single aim; eliminating Gaddafi in the shortest time possible.