In search of Obama's Iraq strategy
President Barack Obama has said that America has a strategic interest in not allowing Islamist militants from the self-styled Islamic State (IS) group to establish a caliphate in Iraq and Syria.
Yet he has so far framed the US intervention in northern Iraq - both military and humanitarian - in limited, if urgent, terms.
His undoubted reluctance to relaunch US military action in Iraq may be understandable for all sorts of reasons. But, for some Obama critics, this is a mixed message that underscores a lack of strategy.
The president insists that he has a long-term strategy.
The administration has framed its current actions narrowly to protect American lives and those of thousands from the Yazidi and other Iraqi minority communities who have fled the latest advances by IS fighters.
And, while the number of US air strikes is mounting, this does not look yet like a full-blown effort to destroy IS military capabilities.
In the short term, the air strikes may work to blunt IS advances on the city of Irbil, and the IS threat to those exposed and desperate on Mount Sinjar. Air drops are also providing those on the mountain with some much-needed relief.
But the US, Britain, and other powers have also been discussing how to get these people off the mountain to relative safety. And some commentators have suggested that providing a "safe corridor" and even a "safe haven" will require foreign troops on the ground.
But President Obama has ruled out the return of US combat troops to Iraq. Others too will be very wary of providing protection forces in this way.
It is reported that thousands have been able to escape the mountain, perhaps with the help of Kurdish forces. That may be some relief to Western policymakers. Whether it is a long-term answer to providing a safe environment for those who have fled is another matter.
And what are the chances of US air power as it is currently being employed proving effective? US defence planners clearly hope that it will tilt the balance on the ground enough for Kurdish and Iraqi government forces to take advantage.
But, again, one of the key calculations in the fragile framework of Iraqi politics, and Kurdish aspirations for greater autonomy, is how far to grant Kurdish requests for more weaponry and other military help like surveillance and intelligence.
There is no question that the Kurds are key players here, perhaps particularly for Washington.
President Obama has also hinted that air strikes could continue for some time. There is even the prospect that they might be increased. But he is making that contingent on Iraq's divided politicians burying their sectarian differences and uniting in the face of the IS threat.
This is clearly the critical element to the Obama administration's long-term strategy and hopes. The president has emphasised that there is no US military solution in Iraq, although the prospect of greater US military assistance is clearly being used a lever to encourage political movement, reconciliation, and change.
But is that enough? Even with greater unity, and more US help and advice, could Iraqi government forces push back the IS advances in a way that they have so far clearly failed to do?
The fighters of the Islamic State have undoubtedly confounded their opponents with their military successes, as Mr Obama in effect acknowledged.
After their initial advances, many said they would become overstretched. That has not happened. And there is debate over what kind of threat they represent now.
Are they behaving more like a conventional army, particularly as they acquire more weaponry? Or do they still represent an unconventional insurgency? Are they a "hybrid" threat? How does this affect how to deal with them?
Mr Obama has said that, to counter IS's self-declared "caliphate", Washington needs partners on the ground who can fill the void. The big question remains whether effective partnerships can be forged in Iraq or, for that matter, Syria?