I don't think Europe should insist on arresting Ratko Mladic, the Bosnian Serb general accused of war crimes. That's hardly the side of the debate one wants to be assigned, because Mladic - described as the engineer of ethnic cleansing at Srebrenica and Sarajevo in the 1990s - should be arrested and handed over to the United Nations' war crimes tribunal. But why might it not be a good idea for Europe to insist on it? There are good arguments for linking Serbia's entry into the European Union to Mladic's arrest, but the union isn't making them. Instead....