“Ladies and gentlemen, we got him”: I can still remember the exultant tone of Paul Bremer, the American governor of post-invasion Iraq, as he announced the capture of Saddam Hussein. Mr Bremer’s exhilaration was understandable. But it also pointed to a persistent fallacy that has undermined US foreign policy for decades. You could call it the “Dr Evil syndrome”.

This is the idea, popular in Hollywood, that killing or capturing a “bad guy” is the key to solving a complex foreign policy problem. It did not work out like that with Saddam. And it is unlikely that the Dr Evil theory will fare any better after the killing last week of Qassem Soleimani, Iran’s most feared military commander.

Many of the “bad guys” eliminated by the US over the years were genuinely evil. Those successfully targeted have included not just Saddam and Soleimani, but also Osama bin Laden, the head of al-Qaeda, and Muammer Gaddafi, the tyrannical leader of Libya.