( CNN ) -- The new ISIS offensive in the North of Iraq has both shaken the Kurds and threatened the Yazidi minority with not only genocide , but also cultural extinction . In response the United States early Friday morning used airpower against ISIS targets inside Iraq . This is the first use of force against ISIS both since ISIS rebranded from al Qaeda in Iraq and since the departure of U.S. forces at the end of 2011 . So what can U.S. airstrikes accomplish ? Airpower is incredibly potent when properly used , but nearly useless in the wrong situations . ISIS will present both these alternatives in Iraq . Put very simply , airpower is incredibly effective against an enemy who is on the offense . If an enemy—be it a person or a vehicle or a weapon system—is on the move and/or fighting , they create a `` signature '' that is easy to spot from the air . Since there will be no U.S. forces on the ground as target designators or air controllers , being able to see a target from the air will be crucial . So , a column of ISIS trucks or—as seen early Friday morning—a captured artillery piece firing against Kurdish positions , each make easy acquisition . Against these targets , airpower is nearly invincible . One thinks of the devastation released over two decades ago by U.S. airpower on the `` Highway of Death '' ( albeit these forces were not attacking , but retreating—but the signature is the same ) . So when President Obama talks about targeted airstrikes to protect American personnel in Baghdad or Irbil , he is , in essence , saying that if ISIS attacks toward these cities , we will use airstrikes on their then-vulnerable forces . Note that the President did not say that airstrikes would be used to eject ISIS forces from Mosul or Kirkuk or Fallujah . For in densely populated cities like these , airpower has real limitations . An enemy in defensive positions , particularly in urban terrain , is very difficult to engage with airpower . Even if the target can be hit , the possibility for collateral damage that causes civilian casualties is very real . And if the target is missed , the collateral damage can be exponentially higher , even catastrophic . So while mission creep is always a danger in any war , in this case the chances of it seem rather minimal . The President has chosen one means—airpower—and given it a mission at which it excels ; prevent enemy forces from attacking prepared positions , whether in Irbil or Baghdad . This mission is well within the capacity of U.S. airpower . When and if unleashed , U.S. warplanes can absolutely prevent ISIS from moving against these two Iraqi cities . But reclaiming territory from ISIS will be another matter altogether . This will require a unified Iraqi effort—Arab and Kurd alike—under a new government with the will , legitimacy and resolve to accept the casualties that a ground offensive will require . We need only look at the U.S. experience in Second Fallujah—almost 10 years ago now—to picture what this might look like . Nor will U.S. ground forces be joining in this endeavor . This must be clear . There is no—zero—appetite in the U.S. public for such a commitment . To that end , we must hope that Iraq remains on its constitutional timeline so that a new government can be formed and begin the long , hard task of regaining control over its territory . Therefore , new Iraqi President Fuad Masum must charge the largest bloc in the Iraqi parliament with forming a government . Soon . Join us on Facebook.com/CNNOpinion .
U.S. strikes ISIS targets in Iraq to stem the group 's spread . General Ollivant : Air power can be very potent when used properly . He says it works well to stop the enemy from offensive moves . Ollivant : Air power often works to stop forces from defensive positions .