There are no solutions only trade-offs

or so said Tom Sowell. At Offsetting Behaviour Eric Crampton notes that, Some days, you just can't get rid of a dictator. He writes,

The New York Times suggests one impediment to getting rid of Qaddafi is that there's no place to which he can flee and consider himself safe from prosecution.

Qaddafi of course should be prosecuted in a first best world. But if we're choosing among second best worlds, the one where he has an exit option and lives on without being punished - and his people are freed - rather likely dominates the one where he doesn't and has to fight on 'till the end.

The trade-off here seems to be between making sure that would be dictators know they will be held accountable for their actions which (hopefully) will make it less likely that they will become dictators in the first place and the fact that holding dictators accountable makes it less likely they will want to give up power.

A trade-off for which there is no first-best solution.