Still, there’s another aspect of Machiavellian thought relevant to the drone debate. This is a core weakness in his thought. He puts too much faith in the self-restraint of his leaders. Machiavelli tells us that men are venal self-deceivers, but then he gives his Prince permission to do all these monstrous things, trusting him not to get carried away or turn into a monster himself.

Our founders were more careful. Our founders understood that leaders are as venal and untrustworthy as anybody else. They abhorred concentrated power, and they set up checks and balances to disperse it.

Our drone policy should take account of our founders’ superior realism. Drone strikes are so easy, hidden and abstract. There should be some independent judicial panel to review the kill lists. There should be an independent panel of former military and intelligence officers issuing reports on the program’s efficacy.

If you take Machiavelli’s tough-minded view of human nature, you have to be brutal to your enemies — but you also have to set up skeptical checks on the people you empower to destroy them.