Bulent Kilic / AFP / Getty Images Syrian rebel leader General Salim Idris, right, and Syria's new opposition chief Ahmad Jarba hold a press conference in Istanbul on Aug. 24, 2013

In the early afternoon of Sept. 14, a stout, square-shouldered man in his mid-60s, wearing a dark suit, gleaming black tie and a thick, neatly trimmed mustache, stepped off the escalator that had just conveyed him to the first floor of the Wyndham Petek, an upscale hotel on the outskirts of Istanbul, and disappeared into a small meeting room amid a tight cordon of bodyguards.

By the time he re-emerged, some 15 minutes later, U.S. Secretary of State John Kerry and his Russian counterpart Sergei Lavrov had announced a deal to secure Syria’s arsenal of chemical weapons. Any chance of American air strikes against the regime of Syrian President Bashar Assad, at least for the time being, was lost.

The stout, mustachioed man was General Salim Idris, commander of the rebel Free Syrian Army (FSA), and he had followed Kerry and Lavrov’s televised press conference inside the meeting room. He wasn’t pleased.

To the consternation of some of the politicians around him, he also wasn’t inclined to mince words. “We reject this agreement,” Idris told journalists, speaking in accented English, “and we think that the Russians are playing a game to win time for the criminal regime in Damascus.”

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Idris had reserved his most scathing remarks for the Kremlin — “Lavrov and Putin are terrorists, partners in [shedding] Syrians’ blood,” he said — but he also made clear his exasperation with the U.S. “I would like to remind the international community that the Syrian people are dying for more than two years, and nobody is talking about their suffering,” he said, on hearing that Kerry and Lavrov had given the Syrian regime until mid-2014 to destroy its chemical weapons. “We are going to say to our friends in the world: Don’t leave the Syrians alone facing and resisting this brutal regime.”

Just over a week earlier, Idris and other rebel commanders had been poised to follow up U.S. air strikes against Syria by mounting a major offensive. As Kerry’s talks with Lavrov crystallized into the Sept. 14 agreement, so did the feeling — at least among Idris and the rest of the opposition — that the rebels had been hung out to dry.

Idris had come to Istanbul to meet with members of Syria’s main opposition outfit, the Syrian National Coalition (SNC), an umbrella grouping of antiregime figures, many of them longtime exiles. The SNC had assembled here to hold talks with Kurdish factions that had so far refused to join its ranks, discuss the political fallout from the chemical weapons attack in Ghouta and form an interim government.

The talks themselves were closed to the press, but SNC members milled about the hotel during breaks, chatting among themselves and with reporters. Most of them wore suits, some wore long, white robes, and several donned checkered kaffiyehs. One of the more visible delegates, Ayman al-Aswad, boasted an unruly beard of Darwinian proportions. He had decided to stop shaving, he explained, until Assad’s regime went down in flames.

The election of the provisional government had been a foregone conclusion. Only one man, Ahmad Tomeh, a moderate Islamist, former political prisoner and dentist by training, was running for prime minister. He was to receive 75 out of the 97 votes cast.

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The more pressing issue was what to do next. “Before, we were depending on the American decision that Bashar, this murderer, would be punished for using chemical weapons,” Salem al-Meslet, the SNC’s vice president, told me during a lunch break. “But now it is different. We want to see what is Plan B for General Idris and the Free Syrian Army.”

For the time being, al-Meslet said, the opposition would focus on trying to parachute its newly formed government into rebel-held areas. “We want this government to be active on the ground in the liberated areas, on the border checkpoints, in the oil fields,” he said. “These areas should be run by civilian authorities, not by [insurgents] with guns in their hands.”

For the provisional authorities to set up shop inside Syria, the FSA and Idris would have to provide them with some degree of security. But even that could turn out to be “very complicated,” Idris himself acknowledged. “We don’t have effective air defense against jets of the regime and against Scud missiles.”

What Idris did not say, but what must have been on everyone’s mind, was that the SNC doesn’t enjoy much legitimacy among the rebels to begin with. To many of the fighters on the front lines, the grouping is little more than a hotel government, a collection of exiles who might have powerful backers — particularly Saudi Arabia — but little sway with Syrians on the ground.

One faction that would never recognize the SNC’s authority in Syria, acknowledged Khaled Khoja, the group’s Turkey representative, were Islamist militants. “Al-Nusra and the [Islamic State of Iraq and Syria] won’t allow this body in Syria,” he said, “because it is in competition with their project to establish a Shari‘a state.”

Several hours after Idris’ presser, the SNC members convened for an inaugural address by their new prime minister, Tomeh, and a rare photo op. Near the back of the long, brightly lit conference room, far away from the handshakes and hugs that followed the speech, sat Aswad with the long, untamed beard. He looked forlorn and pensive, thinking, perhaps, of the day he would finally shear his beard, and that it was not near.

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