Watch more of Charlie Rose's interview with David Petraeus Thursday on "CBS This Morning."
NEW YORK -- The U.S.-led coalition is keeping up air attacks on ISIS targets in Iraq and Syria. Yet, the Islamic terror group still controls important territory and cities, including Palmyra in Syria and both Mosul and Ramadi in Iraq.
Former CIA Director and retired General David Petraeus, who has commanded U.S. forces in Iraq and Afghanistan, spoke with Charlie Rose on the "CBS Evening News" about the challenges the coalition faces in the fight against ISIS.
The situation on the ground in Iraq and Syria is "worrisome," Petraeus said, calling the loss of Ramadi to ISIS "both an operational and a strategic setback, a significant one."
"This is a moment, I think, when you sit back and say, 'What do we need to do in the military arena? What also do we need to do in the political arena?'"
ISIS is "clearly a threat to the United States, to our allies and partners around the world, and of course, very much in the region, where it's fomenting instability, violence and so forth -- and indeed, far beyond Iraq and Syria," Petraeus said. "It's also into North Africa. It's even trying to recruit in Afghanistan and Pakistan."
As far as the strategy to fight ISIS, Petraeus said the U.S. military needs to reevaluate its strategy.
"I don't know that you need a whole new strategy. What you need to do is look at what you have, figure out where you need to augment," Petraeus said.
Among the possible changes he outlined would be adding advisers at the brigade or battalion level, rather than the current division level, and deploying joint tactical air control teams on the ground -- despite the risk of losing American lives.
"There is risk, but there is also risk of losing this fight," he said.
Petraeus said allowing the participation of Iraqi Shiite militias with ties to Iran would be "a very last resort."
"What we need to do is focus not just on the military," Petraeus said. You can't kill or capture your way out of an industrial strength insurgency like this, Charlie -- really, an industrial strength conventional force, because that's what ISIL has actually come to be. You need to have the political component, and without that, without that, you're not going to solve the problem."
Asked if the U.S.-led coalition is winning or losing against ISIS right now, Petraeus responded, "These are fights where if you're not winning, you're probably losing, because time is not on your side."
He went on to say it's "arguable now in Iraq, we'll turn it around. We will win again in Iraq, I do think that Iraq can definitely be handled. I think that it can be kept intact.
However, "We've got to do a lot more in Syria," according to Petraeus.
"This is already a long war, it's become longer because of the advent of the Islamic State, and we have to recognize that. And we have to be in it."