WASHINGTON — US Defense Secretary Ash Carter is "prepared" to change the rules of engagement against the Islamic State group, better known as ISIL or ISIS, he said Thursday morning.

Speaking on the MSNBC program "Morning Joe," Carter was asked directly if the Pentagon was willing to change the rules of engagement, a touchy subject for supporters and critics of the Obama administration's air campaign in Syria and Iraq.

"We're prepared to do that. We've reviewed them the way we review them all the time," Carter said. "If you look at the data, the thing that most enhances the impact of the air campaign is better and better intelligence. We're prepared to change rules of engagement; we've changed tactics, as we just did in the case of the fuel trucks."

The reference to fuel trucks comes after the US destroyed 116 fuel tankers outside Al-Bukamal with airstrikes. About 45 minutes before the strikes began, leaflets were dropped warning the drivers and nearby civilians to abandon the convoy or be killed in the attack.

Explaining why the US has just begun striking at the oil pipeline supplying ISIL with funding, Carter pointed out that "the oil infrastructure is something that the civilian population benefits from. You don't want to punish people."

That concern about harming civilians is at the heart of the fight over the rules of engagement, an issue that cropped up almost from day one of the air operations.

Critics of the Obama administration's strategy against ISIS have argued that the Pentagon is limiting itself on the use of air power.

The easy comparison has been between the strike totals of Operation Inherent Resolve, which has launched about 8,000 strikes over the last 15 months, and the less-than-two-month Desert Storm air campaign in 1991, when the US-led coalition launched 48,224 strike sorties, or an average of 1,100 a day.

However, the limits are there for a reason, Pentagon officials have argued, pointing out that ISIS has put itself among the civilian population and that the US puts a premium on avoiding civilian casualties.

Speaking in Dubai on Nov. 7, Air Forces Central Command head Lt. Gen. Charles Brown Jr. disagreed that the use of airpower has been handcuffed, in particular the argument that some civilian casualties may be acceptable if it means wiping out the greater threat that is ISIS.

"Part of our coalition's [goal] is to minimize civilian casualties," Brown said. "Part of this is getting the population to decide who is on their side, the insurgency or the coalition. And if we just start wiping out civilians, there is potential there that they go differently."

During the Thursday interview, Carter said he agreed with French President François Hollande that the fight against ISIS is a "war," and also called for greater assistance from the other European powers.

"I think Francois Hollande has said it very well. I'm glad the French are galvanized in joining the fight now," Carter said. "As a consequence of the Paris attacks, France has indicated a willingness to do more, I hope the [other] European countries do more than they have done so far."

Carter also used the interview to call again for an end of the "herky jerky" budgeting process that he has said harms the Pentagon's ability to do long-term planning.

Email: amehta@defensenews.com

Twitter: @AaronMehta

Aaron Mehta was deputy editor and senior Pentagon correspondent for Defense News, covering policy, strategy and acquisition at the highest levels of the Defense Department and its international partners.

More In Defense News