The Islamic State group cannot be defeated unless the United States or its partners take on the Sunni militants in Syria, the chairman of the Joint Chiefs of Staff said Thursday.
“This is an organization that has an apocalyptic end-of-days strategic vision that will eventually have to be defeated,” the chairman, Gen. Martin E. Dempsey, said in his most expansive public remarks on the crisis since American airstrikes began in Iraq. “Can they be defeated without addressing that part of the organization that resides in Syria? The answer is no.”
But Dempsey and Defense Secretary Chuck Hagel, who also spoke at a Pentagon news conference, gave no indication that President Barack Obama was about to approve airstrikes in Syria.
Dempsey also was circumspect in describing the sort of broad effort that would be required to roll back Islamic State.
“It requires a variety of instruments, only one small part of which is airstrikes,” he said. “I’m not predicting those will occur in Syria, at least not by the United States of America. But it requires the application of all of the tools of national power — diplomatic, economic, information, military.”
Even so, Dempsey’s comments were notable because he is the president’s top military adviser, and had been among the most outspoken in describing the risks of ordering airstrikes in Syria when the civil war there began.
In the current battle with the Islamic State inside Iraq, Obama’s military strategy has been aimed at containing the militant organization rather than defeating it, according to Defense Department officials and military experts. Pressed on whether the United States would conduct airstrikes on Islamic State targets in Syria, Hagel said, “We’re looking at all options.”
Any use of air power involves risk, including the possibility that innocent civilians may be hurt or killed, or that a piloted aircraft might be shot down. Airstrikes in Syria would also draw the White House more deeply into a conflict from which it has sought to maintain some distance. But there is also risk in not acting, because it is very difficult to defeat a militant group that is allowed to maintain a sanctuary.
In planning its campaign against Islamic State, U.S. military officers have been contending with a highly mobile force that can move across the Iraq-Syria border with impunity.
To the consternation of U.S. officials, Islamic State has been using captured U.S. equipment, including Humvees and at least one heavily armored troop transport vehicle. U.S. intelligence officials have reported that the group has seized 20 Russian T-55 tanks in Syria, armor that the militant group could try to employ in western Iraq.
According to one U.S. intelligence estimate, Islamic State could not be easily defeated by killing its top leadership. Given its decentralized command and control, experienced militants could easily replenish its upper ranks.
“If there is anything ISIL has learned from its previous iterations as al-Qaida in Iraq, it is that they need succession plans because losing leaders to counterterrorism operations is to be expected,” said one intelligence official, using an alternative name for the group. “Their command and control is quite flexible as a result.”
U.S. officials caution that intelligence experts are still assessing Islamic State’s strength and that pinning down the precise number of its fighters is difficult, in part because it is not easy to identify who is a core member of the group and who might be sympathizers fighting alongside them.
Estimates of the number of fighters that might be affiliated with the Islamic State vary from more than 10,000 to as many as 17,000. That includes an initial vanguard of about 3,000 who swept into Mosul, Iraq, from Syria in early June, and Islamic State reinforcements from Syria since that time, as well as thousands of new foreign recruits and thousands of Iraqi Sunnis, like Baathists, who at least for now are allied with the Islamic State.
The military strategy that the Obama administration has employed to confront Islamic State has been limited. Since Aug. 8, the United States has carried out 90 airstrikes to halt the militant group’s advance to Erbil, to help Kurdish and Iraqi government forces retake the Mosul dam and to protect Yazidi civilians trying to escape from Mount Sinjar.
While U.S. air power appears to have been relatively successful in those limited missions, some military officials say that the only way to deal a major setback to such a mobile adversary is to attack Islamic State fighters throughout the battlefield.
John R. Allen, the retired Marine Corps general who led U.S. and allied forces in Afghanistan, said the United States needed to build up the capacity of indigenous forces in the region to take on Islamic State, but he stressed that there was also an important role for U.S. air power.
“For now, attacking ISIS command and control sites, support areas and critical pathways can do a great deal to begin the process of dismantling the organization,” he said.
Those that have been on the receiving end of Islamic State attacks believe more action is needed.
“ISIS needs to be fought in all areas, in both Iraq and Syria,” said Atheel al-Nujaifi, the governor of Iraq’s Nineveh province, which is now mostly held by Islamic State. “The problem is finding a partner on the ground that can work with them because the jets can’t finish the battle from the sky.”
Those within Syria who have fought Islamic State also have expressed hopes for intervention. When Islamic State fighters tried to take land from the Shueitat tribe in eastern Syria, its men took up arms and fought back - a show of defiance that the extremist group did not forget.
This month, Islamic State retaliated, capturing and killing hundreds of tribe members, some of them slaughtered with knives in the street. Wounded and chased from his village, one survivor reached by phone Thursday said he could not understand why the United States was bombing Islamic State in Iraq but not in Syria, where the group has for more than a year built its base and amassed weapons and fighters.
“I wish we could ask the Americans to hit their bases wherever they exist,” said the man, who spoke on the condition of anonymity for fear of retribution.
When the United States began airstrikes in Iraq this month, senior Obama administration officials went out of their way to underscore the limited nature of the action.
“This was not an authorization of a broad-based counterterrorism campaign,” a senior Obama administration official told reporters at the time.
But the beheading of an American journalist and the possibility that more U.S. citizens being held by the group might be slain has prompted outrage at the highest levels of the United States government.
Obama has harshly condemned the slaying, and on Wednesday Secretary of State John Kerry issued a statement declaring that the group should be confronted “where it tried to spread its despicable hatred” and “must be destroyed.”
Such strong statements have widened the gap between the harsh denunciations of Islamic State and the strategy that the White House has so far employed to confront the group.
And Hagel said Thursday that while U.S. airstrikes had made a difference thus far in slowing the Islamic State advance in Iraq, he expected that the militants would regroup and stage another offensive.
The Obama administration has ruled out sending ground troops into combat in Iraq. Administration officials have also continued to insist that much of the strategy is political: the establishment of a more diverse Iraqi government that would give a prominent role to Sunnis in the hope that it would make Sunni communities less hospitable hosts for Islamic State militants.
But other options are being considered, including increasing the scope and frequency of airstrikes.
“You can hit ISIS on one side of a border that essentially no longer exists, and it will scurry across, as it may have already,” said Brian Katulis, a national security expert with the Center for American Progress, a Washington research organization with close ties to the White House.
As proved during the initial U.S. military mission to rout al-Qaida and the Taliban from Afghanistan after the terror attacks of Sept. 11, 2001, U.S. airstrikes would be more effective if small teams of Special Operations forces were deployed to identify Islamic State targets and call in attacks.
Deploying such teams is believed to be one option the Pentagon is considering. Another step that some experts say will be needed to challenge the militant groups is a stepped-up program to train, advise and equip the moderate opposition in Syria as well as Kurdish and government forces in Iraq.
During his news conference, Hagel insisted that the United States was pursuing a long-term strategy against Islamic State because it clearly posed “a long-term threat,” and at one point invoked the Sept. 11 attacks.
But both Pentagon leaders reflected the prevailing view within the Obama administration — that the United States should not move aggressively to counter Islamic State without participation from allies in the region.