Just when you thought the situation in Syria was stabilizing (despite dueling op-eds), last week saw a new battle begin - dubbed "Expunging Filth". In spite of the catchy name, as the WSJ reports, an al-Qaeda spinoff (a jihadist group known as ISIS) is seizing territory across Syria from the US-backed Free Syrian Army and the Government.
"It's a three-front war," a U.S. official said of the FSA rebels' fight: They face the Assad regime, forces from its Lebanese ally Hezbollah, and now the multinational jihadist ranks of ISIS.
As WSJ notes, the spread of ISIS illustrates the failure of Western-backed Syrian moderates to establish authority in opposition-held parts of Syria, some of which have been under rebel control for over a year. "It's still the case that a majority of Syrians are not up for Talibanization," but given the spread of ISIS, their choices may become increasingly limited.
Leaders of the FSA say that ISIS, an Iraqi al Qaeda outfit whose formal name is the Islamic State of Iraq and al-Sham, has dragged them into a battle they are ill-equipped to fight.
Some U.S. officials said they see it as a battle for the FSA's survival. In recent months, ISIS has become a magnet for foreign jihadists who view the war in Syria not primarily as a means to overthrow the Assad regime but rather as a historic battleground for a larger Sunni holy war.
Estimates on the size of ISIS range from 7,000 to 10,000 fighters. Fighters from ISIS—though it shares the goal of toppling Mr. Assad's Shiite-linked Alawite regime—have frustrated Sunni communities that until recently embraced the military prowess and social services of Islamist rebels, local residents said.
The FSA's fight with extremists is spurring new rebel calls for Western help, after the U.S. put on hold what had looked like imminent strikes on the Assad regime. Instead, diplomacy has taken over, after a U.S.-Russian deal to disarm Syria's chemical weapons.
"It's still the case that a majority of Syrians are not up for Talibanization. Given a moderate alternative, they will choose that."
The other alternative: A lawless north becomes a launchpad for jihadists, akin to areas of Pakistan and the Arabian peninsula.
In recent weeks, ISIS fighters have adopted a strategy of dropping back—taking rear positions—as rebels with the FSA alliance leave for front lines to fight government forces, allowing ISIS to build a presence in towns and villages left without security or services.
As the U.S. threat receded, emboldened ISIS militants ramped up efforts to win local support, said Hamid Ibrahim, a spokesman for FSA leader Gen. Salim Idriss.
"They are telling them: 'We told you that you can't depend on America for freedom. Don't be fooled—you only have us,' " Mr. Ibrahim said.