Fifth, current efforts to prevent attacks by jihadis returning from Syria must be expanded, including the efforts to track (and, of course, stop) those leaving for Syria to fight, and find those returning — now with a network of contacts and new skills. This will require close international coordination, because national police and security forces will have pieces of information that must be assembled, analysed and shared. Much information will be in the hands of the families and communities of these Western jihadis, who must be asked for help in finding them and in countering jihadi recruitment efforts. The messaging used by the jihadis and their backers must be countered, perhaps above all by stressing the strife and indeed the murderous violence among the various groups. Returning fighters must be assessed for possible use in counter-messaging, to see if they have returned disillusioned and willing to prevent other young men from making the mistake they made. All this is obvious to security officials in the West, but the effort they have under way is not yet adequate to the danger we face.

What has been missing in Syria since 2011 is Western, and especially American, leadership and determination, but it is not too late for a new policy. The early goal of a quick departure for Assad and transition to democracy in Syria is now impossible to attain. More disorder and suffering are certain. But Syria need not be an endless source of refugees, a centre of inhuman suffering at the hands of a vicious minority regime, and a worldwide gathering place for jihadi extremists. Needed now are a serious and coordinated effort to assist the nationalist elements of the rebels, and organise assistance for them from others in the region — Jordan, Turkey, Saudi Arabia, Kuwait, the UAE, and Qatar are the most critical — and American (and if possible British and French) willingness to use force directly to punish chemical warfare and erode Assad's air power. Those remain essential steps of a new policy that can over time diminish the tragedy being suffered by the Syrian people and the threat Syria now poses to regional stability and European and American security interests.

It remains unclear whether President Obama's announcement at West Point that he wishes "to ramp up support" for the rebels marks a serious policy change or yet another obfuscation. Certainly that speech gaves no signal that a broad reorientation of administration policy is coming. One can only hope that the growing humanitarian disaster, the spread of war to Iraq, the damage to allies like Jordan, and the dangers of "blowback" to the home front from the growing jihadi presence in Syria will lead to a change of Syria policy in Washington, London, and Paris. The question we face now is which happens first: that policy change, or the explosion of bombs set by our own citizens who returned from war determined to make our capitals the next front.