A restatement on the difference between citizen and world actors, and virtu and virtue with respects to them. This is cobbled together from a discussion I'm having on G+, with different bits from different comments; sorry if it's not entirely coherent. I believe in the separation of Virtú and virtue, and that generally speaking, common folk should not be targeted for extrajudicial killing (or land in prison for thoughtcrime, or similar). When one becomes a dictator, or a spy, or while one's acting as a soldier/mercenary, or one does one of a very few other actions that place one on the world stage, one opens oneself up to such acts, and a separate system of morality (that's much more results-oriented and also much more likely to toss up its hands absent a sophisticated analysis) comes into play. (Note that such acts should never include torture, which as I said is unacceptable under any circumstances).
I support those who killed Qaddafi rather than have him stand trial, and support those who erased the Romanovs from the earth and in doing so cemented the end of the Tsars in Russia). Still, these are for exceptional circumstances, and we want these events to be very rare and carefully thought-out.
Regarding spies, I would expect them to be executed without much of a tear; they knew what they were doing when they undertook that activity. If I ran a country and caught a spy, I would probably execute them either through the law or extrajudicially. If I were on the other side, I would probably not be thrilled but I would entirely accept it. Same as with soldiers dying on a battlefield.