While the world has recoiled in horror at the atrocities committed by
The United States and its Western allies have responded with airstrikes on
But the air attacks on Islamic State fighters in Iraq and contemplation of similar action in war-torn Syria will do little more than temporarily curb the militants' momentum as the international community struggles to find a long-term solution to their destabilizing threat, analysts say.
"There is no short-term fix that will completely defeat this threat, so it's important to differentiate between stopping ISIS' momentum and ending or defeating them as an organization," said Janine Davidson, senior fellow for defense policy at the Council on Foreign Relations. She was referring to the Islamic State in Iraq and Syria, as the group called itself before proclaiming its caliphate two months ago.
Without forces in Syria and Iraq to identify targets and ensure that civilian communities aren't vulnerable, airstrikes alone are unlikely to roll back the Islamic State militants who have seized large swaths of territory in those countries, Davidson said.
Targeted strikes can and have taken out militant positions and training camps and can undermine the group's image as a force "screaming through Iraq with one military success after another," Davidson said. But air power alone won't do more than chase the militants from one stronghold to another or counter their sophisticated use of social media to recruit and raise funds, she said.
In an interview discussing Western states' limited options for containing the militants, she said they should focus on forming regional security alliances with Iraq's and Syria's Middle East neighbors and on reform of the Iraqi government that so excluded and repressed Sunni Muslims that many welcomed the militants when they overran northern Iraq.
The Islamic State battlegrounds and gruesome execution of enemies have become a magnet for aspiring militants around the world, said Christopher Chivvis, a senior political scientist at Rand Corp.
Chivvis estimates the number of foreign fighters who have joined Islamic State and other militant Sunni factions at 10,000, including as many as 3,000 carrying European passports and a "not insignificant number" from the United States. On Tuesday, White House officials confirmed that a San Diego man, Douglas McAuthur McCain, had died in Syria fighting for Islamic State.
"People like to be on the winning team and right now it looks like ISIS is winning," Chivvis said. "They have effectively challenged Al Qaeda as leader of global jihad, offering a different model for what jihad ought to look like -- more violent, more locally focused, but equally extreme."
If the United States and its allies want to combat Islamic State's power to attract disaffected and marginalized Muslims, broad international cooperation is required in law enforcement and intelligence sharing, Chivvis said. He pointed to the U.S. turn at the U.N. Security Council presidency in September as an opportunity to galvanize coordinated efforts to counter the extremists' message.
Like Davidson, Chivvis sees little prospect of Western states collaborating with Syrian President
An independent U.N. investigative commission on Wednesday issued a scathing report accusing all combatants in Syria of inflicting "immeasurable suffering" on civilians, including the Assad government's sarin gas attacks on suburbs of Aleppo a year ago and barrel-bombing of opposition-held villages in the provinces of Idlib and Hama with chlorine gas in April.
Jeffrey Bale, a historian and scholar of political and religious extremism at the Monterey Institute of International Studies, criticized the Obama administration and its European allies for ruling out collaboration with Assad, whom he sees as the lesser of two evils.
"The regime in Syria is fighting for its own survival, using brutal methods and not concerning themselves with civilian casualties. But neither are the jihadists -- they are deliberately targeting civilians and anyone they consider insufficiently Islamic," Bale said.
"We should be collaborating with the Assad regime and with the Iranians, who already have Revolutionary Guards in Iraq, to weaken and destroy the operational capabilities of Islamic State. It's not like we're not doing this anywhere else in the world," he said, pointing out U.S. alliances with authoritarian governments in Pakistan, Saudi Arabia and elsewhere.
"We have to assess what is the No. 1 threat," Bale said. "What would be catastrophic is if Islamic State was able to establish permanent control over the heartland of the Middle East."
Bale also said that the United States and its allies were too timid in their initial strikes against Islamic State fighters when they were traveling on open roads in celebratory convoys after seizing the northern Iraqi city of Mosul in June.
"Whenever we observe Islamic State fighters away from heavily civilian areas we should be launching devastating attacks on them with the full panoply of weapons from aircraft," he said.
"Obviously, once these guys are back in big urban areas surrounded by civilians, it's much more difficult to target them from the air," he said. "Now they are hunkered down using civilians as shields."