LORD CAMERON has form when it comes to imperial sabre-rattling. In his previous incarnation as premier, he wanted the RAF to take on the Syrian and Russian air forces.

It was the unlikely combination of Barack Obama and Ed Miliband that stayed his hand. Miliband led a cross-bench rebellion against British support for US-led air strikes on Syria in 2013.

Now Foreign Minister Cameron trots out the the timeworn justification for the deployment of imperial gunboats (and cruise missiles) as “self-defence.”