At the moment, Moscow and Washington are moving toward a shared aim for negotiations, in which representatives of Assad would have a role. The opposition is bitterly divided over this issue, and has agreed only begrudgingly to enter talks before Assad steps down. For negotiations to succeed, Assad has to believe that his Russian backers are in fact committed to ending the fighting and could abandon him. Otherwise, Assad will either refuse to participate, or like other dictators who know they have the military advantage, string out bogus talks while the killing goes on.
Unfortunately, Moscow is more content with the status quo than is Washington. So far, the United States has done little other than provide humanitarian and political support to the opposition, while Iran does the heavy lifting on the ground to prop up Assad. Russian obstructionism in the Security Council, meanwhile, combined with arms shipments to, and evacuation flights of Russian citizens from Damascus, help sustain Assad without imposing significant costs on Moscow or exposing it to a loss of prestige if the regime collapses.
Changing the Russian position means changing Moscow's calculus on Syria. And that means presenting the Kremlin with an alternative that it finds more unpalatable than the status quo: a NATO-backed, Turkey-led military coalition invited by the Arab League to intervene in the Syria conflict. If Turkish leaders are as serious about taking action as their recent statements suggest, they should be willing to back such a strategy. In addition to Turkey, this force would be made up of key regional actors, including Saudi Arabia and other Gulf States, Jordan, and Egypt. The coalition would train and equip selective opposition militia, while setting the stage for direct military intervention, such as air strikes aimed at Assad's air force. The United States, France, and Britain would play essential supporting roles through NATO, as the United States did for France and Britain in the NATO phase of the Libya intervention.
Even opening discussions about the formation of such a coalition would be difficult for Moscow to swallow in the wake of NATO's successful intervention in Libya. Russia would be confronted with the prospect of seeing its erstwhile ally ousted with the backing of NATO and without the express backing of the Security Council.
None of this, of course, will be necessary if Russia ups the pressure and isolates Assad. A strong regional coalition, led by Turkey, could later become the basis for a U.N. peacekeeping mission that even includes Russia (as in Bosnia and Kosovo). Such a mission could prevent postwar reprisals and help keep Syria from further disintegration.
In short, Kerry's message to the Russians and to the allies should be the same: Washington is now committed to resolving the crisis and is ready to work with you, but will not allow the conflict to continue indefinitely. As ever, there are no guarantees this approach will succeed. But another secretary of state tried the alternative two decades ago and proved that, when faced with an intractable crisis, consultations without commitment to clear objectives is a recipe for failure. John Kerry will need to do more than simply listen to his counterparts if he wants to avoid the same fate on his crucial first trip abroad.