The pressure on Barack Obama's administration to intervene in the Syrian crisis has increased remarkably over the past week, for two principal reasons.
First, there are suspicions that chemical weapons have been used in the Syrian civil war, though only in a limited way so far, by the beleaguered regime of Bashar Al Assad - or possibly by the rebels, who would have obtained such weapons from government stockpiles.
Second, the rebels' advances have stalled as the regime has succeeded in hunkering down and defending a number of critical locations. Defections from the Syrian army and government have been reduced to a trickle.
The Israeli strikes on suspected Syrian missile stocks early this month have further complicated the regional dynamics.
Pressure on America to do something is mounting, not just from within the US but also from regional powers.
King Abdullah of Jordan, who recently visited the White House and whose country is feeling the enormous strain caused by Syrian refugees, implored the United States to take the lead.
And the Turkish prime minister, Recep Tayyip Erdogan, is scheduled to meet President Obama on Thursday, and is likely to use the occasion to make the same kind of plea. The visit comes on the heels of twin car bombings in southern Turkey on Sunday, attacks linked to Syria that will serve as a reminder of the risks Turkey faces from the Syrian conflict.
The Obama administration has so far refused to engage in Syria militarily although the signs are that it may now consider changing its policy, moving towards providing the rebel side with lethal ordnance and related material.
Syria, however, is not an American problem but first and foremost a regional one. The human suffering in more than two years of war has been and is horrific, and is likely to get a lot worse before it is over.
So far the crisis is affecting countries in the region primarily by causing an outflow of refugees. This has increased Sunni-Shi'a tensions, undermined traditional borders, and given rise to new actors, most notably Al Qaeda-linked ones such as the Jabhat Al Nusra.
The regional balances are also being turned upside down: Turkey and Qatar seem to be working together against a coalition composed of Saudi Arabia, Jordan and the United Arab Emirates. All of those countries are nominally on the same side against Iran, Iraq and the Lebanese armed activists of Hizbollah.
While American domestic critics heap much scorn on the administration's reluctance to intervene unilaterally and militarily in Syria, no one has put together a working plan about how exactly America could best intervene - and what the US exit strategy would be.
Instead, the argument that is often advanced is that doing nothing is riskier than doing something. The critics assume (or, to be more accurate, they hope) that things will somehow work out well in the end. But in complex societal breakdowns and civil wars such as Syria's, this is never the case.
We all know that if the United States were to take the lead and intervene, it would end up "owning" Syria and would be committed to rebuilding it.
In the words of former US secretary of state Colin Powell, the proverbial Pottery Barn rule would apply: "If you break it you buy it." Never mind that Syria is beyond broken already.
Interventionists also underestimate the unwillingness of the ordinary people in the region to countenance yet another American military adventure in their midst. More importantly, they vastly overestimate how thankful the Syrian public will be once Mr Al Assad is removed; anti-Americanism is an ingrained phenomenon across the whole region.
So what can be done?
On the eve of the Iraq war in 2003 many regional powers - including the Turks who went out of their way to organise conferences of like-minded states - tried to dissuade the United States from invading by arguing that Saddam Hussein was a regional problem, to be dealt with by the regional countries. There was no need therefore for US boots on the ground.
The Obama administration could now learn from that time and argue that it is willing to support and help any action that the regional states - Turkey would be essential to any such project - might undertake against the Assad regime.
This could entail air attacks on Syrian air defence installations and airbases, in support of a Turkish and allied attempt to create safe havens at both ends of Syria. This could be undertaken on the understanding that under no circumstances would there be any US military units on the ground. At the same time, Sunday's violence demonstrates that Turkey is not insulated from possible Syrian meddling.
This approach is not only relatively safe for the Obama administration, but it is reasonable. If this crisis is directly affecting the regional powers, they need to share the burden of solving it.
It is likely that the Turks and others would recoil at the idea of sending in their own troops; they too have public opinion to heed. It has been easy for them so far to put the onus on the Obama administration.
Were the US to offer its support to a Turkish-Arab intervention in this way, before long the regional powers would have to seriously reconsider their options for acting to end the crisis.
If the regional powers did not step up their response under those conditions, they would still have to face the consequences of the civil war on their own populations, security infrastructure and resources. They would not, however, be able to put the blame on the United States and its western allies.
Henri J Barkey is a professor of international relations at Lehigh University in Pennsylvania
