The other big threat NATO debated at this summit was Islamic State, the Sunni militant force that has taken over huge chunks of Syria and Iraq, murdered journalists and massacred hundreds of people.

A core alliance of 10 nations is to act jointly against IS, but tellingly that does not include an Arab nation, and only one of Iraq’s neighbours, Turkey. The hope is that others will join later.

“I did not get any resistance or push back to the basic notion that we have a critical role to play in rolling back the savage organisation that is causing so much chaos in the region… So there’s great conviction that we have to act as part of the international community to degrade and ultimately destroy ISIL,” said President Barack Obama.

The commitment will not include troops on the ground, but does cover the entire range of other possible military actions in support of Iraqi and Kurdish forces.