Politics aside, there are good reasons to doubt the Kerry-Trump plan for Syria will work. Assuming the cease-fire sticks for seven days, which is no sure thing, is it even desirable for U.S. intelligence officers to be sharing the locations of U.S.-backed rebels in Syria with a Russian Air Force that has been bombing them for nearly a year? (…) Kerry has not grasped this lesson. For more than a year now, he has been trying to get Lavrov to pressure the Assad regime to enter a political process for Syria, and at almost every turn the Russians have failed to deliver on Lavrov’s promises. Kerry has paid a steep price for his diplomatic tenacity and patience. When he was pressing for new political talks a year ago, Russia was building up its air operations in Syria. Kerry did next to nothing to counter those Russian escalations while he was trying to restart the political negotiations. As a result, Russia projected real military power in the Middle East for the first time since the 1970s.“
(Eli Lake: „Kerry Brokers Trump’s Plan for Syria“)