Have US and coalition airstrikes stopped the growth of ISIS? They don’t appear to think so. ISIS launched an attack on a key defense of the Kurdish capital of Irbil, nearly overrunning the major defensive outpost that protects the regional government. Only after several hours of overnight fighting could coalition airstrikes make a difference:

After hours of heavy fighting, Kurdish fighters in Iraq have repelled an assault by ISIS fighters southwest of Irbil, Kurdish officials said.

Kurdish commanders say ISIS fighters had threatened to overrun Kurdish defensive positions in the area for a while, and the two sides were so close that airstrikes were not possible. …

ISIS launched the major assault from several directions Tuesday night near the towns of Gwer and Makhmour.

The towns are about 45 kilometers (28 miles) from Irbil, the Kurdish capital.

CNN’s Tom Lister explains in the video that the real objective here is Mosul, an oil-rich area which ISIS does not yet fully control. They want to push the Kurds and Iraqis all the way out of Mosul, and an attack on Irbil would force the Kurds to pull back to defend the capital. As this attack shows, the defenses are thin around the capital, and the Kurds have to begin prioritizing their defenses, especially given the critical lack of arms and defensive armor they possess, thanks in part to a reluctance by the coalition to directly arm the Kurds.

However, that’s not the only reason why ISIS wants to go after Irbil. If Irbil falls, then so does all of the organized opposition to ISIS in the north. Turkey isn’t exactly putting pressure on ISIS, and Iran won’t venture out into Kurdistan without an explicit invitation, or unless the Kurds collapse. Kirkuk and its oil resources would fall easily into ISIS’ hands, as would the hundreds of thousands of refugees and millions of Kurds who would have nowhere to escape the genocide that would occur.

Clearly, ISIS is not a force in retreat in any sense other than tactical and temporary. They have initiative, and they are probing Iraqi and Kurdish defenses to strike a massive and fatal blow to their enemies. They came close to achieving that this time, and unless the anti-ISIS coalition starts coming up with better plans and some real ground forces, the defeat of the Kurds may be inevitable. And that would be a disaster of such immense proportions that it’s almost unimaginable, not just militarily and strategically, but especially in humanitarian terms.