Following 9/11, there has been a growing recognition in the Pentagon that the "soft power" of overseas aid helps in the fight against extremism. If America is seen to be indifferent to, say, the Ebola crisis or a huge earthquake, it can act as a recruiting sergeant for radical groups. There are some signs that Mr Trump might be persuaded by this argument; that aid and security go hand-in-hand.

Taliban fighters posed for the camera, their shawls and bandannas covering their identities but not their jubilation, as they captured the main roundabout in the northern Afghan city of Kunduz early this month in what could have been called “operation hoist the flag and pull out a smartphone.” [...] In a country where social media use is becoming more and more vital, the Taliban are making sure to flood the information channels with their message.