Syrian opposition fighters appear to be making significant gains on the battlefield this week, following an offer by their top political leader for negotiations with the regime of President Bashar al-Assad.

This military and diplomatic news may appear positive. But Syrian sources caution that the battlefield advances may accelerate movement toward a breakup of the country, as Alawite supporters of the regime retreat to their ancestral homeland in the northwestern region around Latakia. And there’s no sign that either Assad or his Russian patrons are paying any more than lip service to a political settlement.

One potential game-changer is a request for U.S. help in training elite rebel units, which has been drafted by Brig. Gen. Salim Idriss, the new commander of the opposition Free Syrian Army. In a letter dated Feb. 4, he seeks U.S. assistance in “training for: (1) special operations; (2) international humanitarian law; and (3) . . . in chemical weapons security.”

Idriss requested various supplies for these elite units, including: “(1) combat armor; (2) night vision goggles; (3) hand held monocular and longer range spotting equipment; (4) strategic communications; (5) winterization packs; and (6) tactical communications.”

This request for assistance was made just after the Assad regime had rebuffed an offer by Sheik Ahmad Moaz al-Khatib, the head of a new opposition coalition, to negotiate with government representatives.

The rebels’ recent military successes have come mostly in northern Syria; the attacks were made by different battalions that appear to operate with little central command and control. The gains include:

●The al-Jarrah air base, about 30 miles east of Aleppo, which appears to have been overrun by fighters from Ahrar al-Sham, a battalion based in Idlib. Videos posted Tuesday by the rebels showed them walking past derelict Syrian warplanes and inside a fortified hangar containing what appeared to be two Czech-built ground assault planes. On camera, the rebels displayed dozens of bombs racked in a warehouse, and other ammunition and spoils of war.

●The Thawra hydroelectric dam on the Euphrates, which is one of Syria’s biggest power-generating facilities. Rebel sources said the Syrian army gave up the strategic dam after army positions there were overrun. The rebels negotiated a surrender with regime loyalists who remained. These sources said the dam continues to operate and provide power — a positive sign for those who worry that Syria’s infrastructure would collapse if the rebels took over.

●The Aleppo International Airport, southeast of the city, is close to falling. Free Syrian Army sources said Tuesday that their fighters, including allies in the extremist al-Nusra Front, had captured an access point near the airport known as “Liwa 80.” Syrian sources said rebels there had seized large amounts of ammunition, including some shoulder-fired anti-aircraft missiles.

●Damascus and its suburbs, where the rebels are tightening their squeeze on access points to the capital. Syrian sources said fighters are converging on Damascus from different parts of the country, expecting a decisive battle there soon. “Regime forces are suffering from very low morale, whereas FSA soldiers have been encouraged by recent positive developments,” asserts one FSA report from Damascus.

The al-Nusra Front has been a catalyst and beneficiary of the rebels’ success. According to Syrian sources, al-Nusra is gaining strength in Homs, a city in central Syria where the group was never strong. One Syrian source told the State Department: “They have money, they are helping people with everything including daily living supplies. I heard that some fighters are leaving their [former] brigades and joining [Al-Nusra], some of them selling their weapons to feed their families.”

One Syrian who works closely with the Free Syrian Army explained how creating an elite commando force could help check Syria’s drift toward becoming a failed state: “We still believe FSA on the ground is still needed badly to tip the power and support other parallel solutions, including the political one. But FSA [has] become a jungle. . . . My recommendation is . . . to start working on elite [forces that can] . . . initiate key attacks plus help as a buffer from potential warlords and fights among fragmented FSA factions. Plus, this unit can handle other key tasks, like securing chemical weapons.”

This Syrian strategist argues in another memo that the rebels must “speak to the silent majority, many who did not care about the revolution, and they want their life back.” He said that such a negotiated settlement requires more pressure on the United States, Russia and the United Nations “to find a way out of the deadlock.”

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