In One Week Al-Nusra Showed They'll Either Win Or Destroy The Syrian Revolution

It appears Jabhat al-Nusra — the most fearsome Syrian rebel fighting force — led another successful attack as the opposition captured its first major military airport, Zeina Karam of The Associated Press reports.

But the al-Qaida affiliated group has also been accused of assassinating the northern commander of one of Syria's largest rebel group, according to Khaled Yacoub Oweis of Reuters.

The events, which both happened Wednesday, show how Nusra has evolved into both the opposition's biggest asset and its biggest liability.

After months of fighting at the Taftanaz air base in the northern Idlib province, about 700 rebels from "Nusra and other Islamic groups" commandeered much-needed ammunition, tanks and rocket launchers from the sprawling base.

Taftanas is considered the north's largest base for helicopters used to bomb rebel-held areas and deliver supplies to government troops. Karam notes that it's unclear if the opposition will be able to hold Taftanas as government bombed the air base on Friday.

Meanwhile in a rebel-held position near Turkey's border, assassins in a white car gunned down Thaer al-Waqqas, northern commander of the Muslim Brotherhood-backed al-Farouq Brigades. Farouq blamed Nusra since Waqqas was suspected of being involved with the killing of a main al-Nusra leader four months ago and the leader's brother vowed revenge.

A rebel in the area told Reuters that "it seems a matter of time before the clashes with Nusra erupt" near the border crossing, which is controlled by Farouq and its Sham Hawks Brigade ally. Oweis notes that there was already tension between the hardline Islamic Nusra and opposition groups like Farouq that include a lot of defectors from Assad's regime.

Adding to the risk of infighting, the three large rebel organizations aren't under the umbrella of the newly formed West and Arab-backed rebel command structure. In November the U.S. designated Nusra — which has grown to about 5,000 fighters or about 10 percent of the opposition force — a terrorist organization.

The disparate groups will have to find a way to co-exist, as a steady stream of foreign fighters will be crucial to toppling Bashar al-Assad, who has barricaded his regime in the center of Damascus and is counting on superior air power to beat back the rebels.

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