Our indefatigable outgoing Secretary of State John F. Kerry is engaged in a furious if implausible diplomatic effort to strike a deal with Russia to end the siege of Aleppo. He is motivated not just by the scale of the humanitarian crisis in the Syrian city but also by the prospect that the incoming president will strike a different kind of deal with Moscow, one that abandons the Syrian opposition and places the United States squarely on the side of dictator Bashar al-Assad.

The State Department is not advertising Kerry’s quiet mission, following the quick collapse of the last U.S.-Russia cease-fire agreement he struck. But behind the scenes, Kerry is spearheading a process that seeks to stop the brutal bombing campaign that the Assad regime and its Russian partners are waging in eastern Aleppo, which has included the targeting of hospitals and the siege of a quarter of a million starving civilians.

Four administration officials described the effort to me as a long shot at best, but also the only chance to persuade the Syrian and Russian governments to halt the killing. “We are still actively trying to push it,” one official told me. “We are not giving up on this. We think we need to give it a chance.”

The strategy is to narrow the focus of the negotiations to cover Aleppo only, and to broaden the format to include Saudi Arabia, Qatar, Turkey and, at times, Iran. The deal would be an agreement by the Syrian opposition to separate from members of the al-Qaeda-linked Jabhat Fatah al-Sham, or Syrian Conquest Front (and formerly the al-Nusrah Front), whose fighters would leave eastern Aleppo. In exchange, the Assad regime and Russia would end the siege and allow aid to flow.

There have been several meetings between U.S. and Russian diplomats in Geneva to discuss the deal, and Kerry has been conducting bilateral discussions with all the players. He speaks to Russian Foreign Minister Sergei Lavrov about twice a week and met with him this month in Lima, Peru. Kerry met with allies to discuss the plan this month in Abu Dhabi, United Arab Emirates.

There are already multiple roadblocks. The United States and Russia cannot agree on how many Conquest Front fighters are in Aleppo. Also, there’s a dispute over whether the Assad regime will determine who governs eastern Aleppo if the cease-fire holds. One senior administration official told me that Russia is simply buying time to either achieve its aims militarily or wait for the Trump administration to come in and offer better terms.

“The Russians are trying to force the city to surrender,” the official said. “They only need 60 more days. And they’ll get it.”

Officials acknowledge that a frustrated Kerry still has not been given authority by the White House to bring any meaningful pressure to bear against Assad or Russia, placing him in a weak negotiating position. The prospect of Hillary Clinton being elected president gave Kerry some leverage, because she was expected to pursue a more hawkish Syria policy, officials said.

That measure of hope all but vanished when Donald Trump won the election. Why would Moscow cut a deal with Kerry when Vladi­mir Putin can wait two months and cut one with Trump, who campaigned on a promise to work with Russia? Trump seems to agree with Putin that the Syrian opposition can’t be trusted and that Assad remaining in power is better than the alternative.

Fears about Trump’s plan for Syria rose last week when the Wall Street Journal reported that Donald Trump Jr. met in October in Paris with the elements of the Syrian opposition that Assad and Russia endorse. Donald Trump told the New York Times last week he has “some very strong ideas on Syria.” He has spoken with Putin twice since the election about cooperation in the Middle East.

Moscow and the segment of the Syrian opposition it supports are seeking a peace deal that would cement Assad’s rule for the foreseeable future and label the rest of the opposition as terrorists to be destroyed. Many in Washington, including Rep. Tulsi Gabbard (D-Hawaii), who met with Trump last week, argue that the United States should stop supporting Syrian rebels to end the war and stop the suffering.

It’s a tempting prospect, but it’s based on flawed logic. If Trump strikes a deal with Russia and the Assad-friendly opposition, he will be able to claim success where Kerry failed. But it will be a pyrrhic victory at best. The rest of the opposition will continue fighting, and millions of Syrians will continue to resist Assad’s brutal rule and demand basic rights.

Even worse, the United States will have placed itself on the side of those committing war crimes and crimes against humanity, alienating most Syrians for a generation and driving them into the arms of extremists, all for a false peace. Kerry is right to work to avoid that disaster.

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