海角大神

Only two grisly questions remain in Syrian President Bashar al-Assad鈥檚 fight against his civil war rivals: how long before the last major armed resistance, in the northwestern province of Idlib, is聽defeated; and the fate of the estimated 3 million civilians who are in effect trapped there.

Yet even amid preparations in recent weeks for a final assault, a different battle has been taking shape: among outside powers in the seven-year war, each with its own interests. How that ends will have implications not just for Syria, but the wider Middle East, Europe, and for the balance of power between Russia and the United States.

Even were this political wrangling to resolve itself, it could be years before Syria recovers, much less reconciles. Hundreds of thousands of civilians have been killed, many in attacks on residential areas, hospitals, and aid workers. More than half the country鈥檚 pre-war population of 22 million has been forced to flee: to neighboring Turkey, Jordan, and Lebanon; to Europe; or elsewhere inside Syria.

But the postwar geopolitics could prove almost as daunting, given the number of powers involved and their rival agendas. It鈥檚 the equivalent of three-dimensional geopolitical chess, with a scorecard needed merely to make sense of what may lie ahead.

Vladimir Putin is central. Having provided arms to the Assad regime, Russia intervened directly in 2015, once it became clear neither the US nor its European allies had the political stomach for doing so. Mr. Putin鈥檚 move carried relatively little military risk. It largely involved air strikes against rebel-held areas with little or no missile defense. Russia鈥檚 gains, however, included a beefed-up naval presence at the Mediterranean port of Tartus, an airbase near Latakia further up the coast, and its most significant Middle East footprint since Soviet times. Without Russian air power, Mr. Assad鈥檚 Army would not have been able to turn the tide in the war.

聽Next, there鈥檚 Iran. Its forces and client militia fighters 鈥� chiefly Hezbollah, from neighboring Lebanon 鈥� have been Assad鈥檚 other indispensable ally. Iran now has a presence on the ground, part of a potential 鈥渓and bridge鈥� of military and political influence stretching from Tehran through to Lebanon.

Israel largely stayed out of the war, but has a core strategic interest in Syria: to keep Iran from establishing a permanent military presence, or funneling more powerful weaponry to Hezbollah. In a relationship driven by realpolitik on both sides, Prime Minister Benjamin Netanyahu and Putin appear to have struck an understanding that is holding at least for now: we will attack Iranian forces and facilities we deem a threat to our own security, but will make sure not to hit Russian forces.

Turkey, bordering Syria, has a dozen observation posts in Idlib. With NATO鈥檚 second-largest army after the US, it has forces inside northern Syria. Turkey鈥檚 interests include ensuring that Kurdish fighters there 鈥� key US allies in the fight against ISIS 鈥� leave. It has been pressing Putin, Iran, and Assad to hold off from a full-scale assault in Idlib. And this week, he appeared to have won a key concession: an agreement with Putin to create a buffer zone in the province between Syrian government and rebel forces. If indeed the Russian president鈥檚 reported demand that 鈥渞adically minded鈥� jihadists pull out of the area is met, a final military showdown could yet be averted. In the meantime, having sealed off the border, Turkey has also been driving home its determination to prevent a further mass flight of refugees. Some 3.5 million are already in Turkey.

Europe is equally concerned to avoid a new refugee crisis. Just such an exodus, in 2015, empowered stridently anti-immigrant politicians in a number of European Union states and has caused lasting fissures within the EU.

The United States may have the most complex challenge of all. The US has some 2,000 Special Forces troops in Syria, as part of its campaign against the Islamic State. President Trump has said he wants to bring them home. But he has also made curbing Iran鈥檚 widening regional influence a foreign-policy priority. His hope, presumably, is that a combination of Israel鈥檚 military power, Turkey鈥檚, and Russian cooperation can achieve that. But he is embroiled in a tariff war against Turkish President Tayyip Erdogan over his failure to release a US cleric. And US military and security figures have been arguing for a need to restrain Russia鈥檚 resurgent influence and assertiveness.

Assad, himself, seems on course to emerge unchallenged as Syria鈥檚 leader, something that looked highly improbable before Russia鈥檚 intervention. Yet whether he remains for the longer term will depend on the key outside players. The US, Europe, and Turkey were all against his staying in power during the early stages of the war. At least for now, however, Putin seems in favor of Assad staying. As long as that鈥檚 the case, it is hard to see how anyone else will, or can, force him out.