The US has a tiger by the tail in trying to deal with Isis. President Barack Obama has a couple of successes in his air campaign. But real limits, some of them obvious, are already showing in the late-starting struggle against the Al Qaeda offshoot that effectively controls roughly a third of the old colonial constructs of Iraq and Syria.
US air power quickly succeeded in relieving most of the pressure against besieged religious minorities. And working with Kurdish troops and a smattering of Baghdad regime special forces, US air power played the critical value-added role in dislodging the world's richest terrorist organization from its control of Mosul Dam, the largest dam in Iraq.
But when Baghdad regime forces tried again to recapture Tikrit, hometown to the late US-deposed dictator Saddam Hussein, they got their butts handed to them for a third time. No US air power was employed in the effort.
Why not? Too great a risk of civilian casualties in a populated area. Which is a limitation that suggests that Isis will hold on to most of the cities and towns it has seized this year.
And then, speaking of limitations, there is the death by filmed beheading of American journalist James Foley. Having publicized this grisly act of murder, Isis threatens the same fate for another American journalist it holds hostage, Steven Sotloff.
The threat is clear. Stop interfering with Isis or have another dead American journalist, with more terrorist acts on the way.
Again, we run up against limits.
For earlier this summer, Obama sent ultra-elite Army Delta Force commandos on a raid in northern Syria to rescue the journos. But when the team arrived, the American hostages were gone.
With all the territory that Isis has seized, the organization has no shortage of places for hiding hostages.
In the event, the special forces operators quickly found themselves with both an empty cupboard and a fierce firefight on their hands, and withdrew.
So large and wealthy has Isis become this year that it is like operating against a nation-state.
So, more than a week after beginning, the opportunities and challenges, possibilities and limits, of Obama's new intervention are coming into focus.
The great bulk of aerial sorties -- carried out by Navy and Air Force piloted aircraft and drones -- have been in support of the Kurds, the only consistently pro-US constituency left in "Iraq." Reports indicate that these strikes served to clear the way for recapture of Mosul Dam, though ground fighting and air strikes still continued nearby at least through yesterday, and to relieve what limited pressure Isis was placing on the Kurdish capital Erbil.
The pro-Kurdish piece of this is working.
We've also learned that that we can deliver on a humanitarian mission when we have to, a heartening thing to know in a crisis which may require more that before this all plays out.
However, we also know that we have played to our strength in working the Kurds on missions outside urban areas.
The Obama administration spent months in a political game to try to force out the fiercely Shia-centric prime minister, Nouri al-Maliki. During this long delay, Isis was allowed to grow ever stronger and more entrenched.
Maliki's finally been edged aside. But his successor, also approved by Iran, has pledged allegiance to the same doctrines as Maliki. And given American concerns about avoiding civilian casualties, the US intervention might not be much use in regaining cities and towns lost by the Baghdad regime.
Now, with the beheading of James Foley, Isis has upped the ante. If we continue to hit them, there will be more brutal acts of terror against Americans. It will be interesting to see how that affects US public opinion, which has tilted away from isolation toward slightly favoring the limited air intervention.
The huge delay in hitting Isis while pursuing the dubious goal of picking a less tainted pro-Iranian prime minister of a collapsed country is not the Obama administration's only military mistake in favor of politics. For Obama won't hit Isis inside Syria.
Why not? Because that would help the Assad regime, which actually is a functioning government despite the Syrian civil war which Obama narrowly avoided being drawn into the middle of, and which has no agenda against the US. In reality, Russia and Iran were never going to let Assad fall.
If Obama is serious about effectively containing Isis, much less ultimately defeating it, he's going to have to let go of some very non-serious thinking.