Syria has become the worldâs endless nightmare. The war has entered its third year, causing more than 100,000 deaths and displacing millions. Short of a full-scale foreign military intervention that enables one side to achieve a decisive victory, the combatants in Syria are likely to remain locked in a war of attrition, which has transformed into a theater of proxy confrontations between Arab states and Iran; Russia and the West; Sunnis and Shias. Against the backdrop of tepid negotiation attempts, the debate in Washington has focused on whether to continue to arm the Syrian opposition or to mount airstrikes if Bashar al-Assadâs regime violates certain âred lines.â But the nature of the Syrian war has changed: the international community is now a party to the conflict. Because of this, the time has come for the United States to shift its focus to launching a robust, consistent diplomatic operation.

Civil wars end when one opponent wins; when combatants negotiate an agreement; or when the parties reach (or perceive to reach) a stalemate. The latter often plays out as a scenario in which neither of the sides is able to attain a military victory and, because of massive fatalities, depleted ammunition, and/or loss of external support, seeks to break out of the painful deadlock.
In Syria, the rebelsâ support from Sunni extremists as well as the Gulf states, and the West and Assadâs backing by Iran, Russia, and the Shia militant movement Hezbollah make a definitive military victory by either side unlikely in the short run. A political solutionâthe most desirable outcomeâhas thus far proven elusive, not least due to the cleavages in the international community. As it stands, Syriaâs war is unlikely to end until the adversaries arrive at the kind of stalemate described above. The problem is it may take yearsâeven decadesâuntil they reach a deadlock too painful to endure.
Consider the civil war in Lebanon from 1975 to 1990 or the conflict over Nagorno-Karabakh during the late 1980s and early 1990s. One of the reasons these conflicts became so protracted and brutal was the unconditional support that the different sides received from outside powers in the form of materiel, manpower, training, logistics, financing, and sanctuary. The Israeli, Iranian, Syrian, and Western interference in the Lebanese civil war, and Turkish and Russian involvement in the Nagorno-Karabakh conflict persuaded combatants on both sides that they could prevail, thus discouraging them from coming to the negotiating table.
When the war in Syria broke out in March 2011, the United States and its allies had the opportunity to preclude the conflict from morphing into a regional sectarian war. A no-fly zone, coupled with timely and substantial Western military assistance to the Syrian opposition, could have assuaged the conflict in its early days.
But two years laterâafter we have seen the war engender shockwaves in Iraq, Jordan, and Lebanon, becoming a standoff between regional and international heavyweightsâa military intervention will likely freeze the conflict rather than resolve it. (In 1974, the intervention of the United Nations peacekeeping force in Cyprusâin the wake of ethnic cleansing, a military coup against the Greek Cypriot government, and Turkeyâs invasionâonly congealed the de facto partition of the island without achieving a settlement between its Greek and Turkish communities, backed respectively by the governments of Greece and Turkey. After 39 years, the peacekeeping force is still there.)

Providing military support to the Syrian regime and its oppositionâwithout simultaneously exerting tangible pressure on both sides to make steps toward a political solutionâportends a longer and bloodier war. The Syrian conflict has long passed the point where the opponents are willing or able to reach a solution by themselves. The Assad regime will not accept a political transition while receiving active support from Iran, Russia, and Hezbollah (and tacit backing from Iraq). The rebels, for their part, are unlikely to give up as long as they are backed by Arab Sunni states and anticipating reinforcement from the West. Syriaâs civilians, who have suffered displacement and atrocities, have grown polarized and fearful of rival sectarian and ethnic groups. And the spoilersâsuch as al Qaeda affiliate the al Nusra Frontâwill continue to exploit the Syrian war and promote their agendas by conflagrating sectarian violence in the region.
As long as the warring sides receive unconditional support from their patrons, they will have no incentive to lay down arms. And so, to begin with, the Western governments and their regional counterparts should reevaluate the conflict, identify common end goals, and find a zone of agreement. They should employ strategicallyâby attaching stringent conditions to itâthe security assistance that they provide to the combatants, so as to compel the Syrian regime and its opposition to come to the negotiating table. They have the stakes to strike a consensus among themselves and the leverage to urge their Syrian clients to make the concessions required for peace. Indeed, international leaders should heed to the lessons of history to avoid the deleterious effects of the continued fight in Syria.
The current stalemate may not be costly enough to force the warring sides to negotiate peace. But it is hurting millions of innocent civilians. It is also hurting Washingtonâs interests, by destabilizing its regional allies, boosting Iranâs influence, perpetuating sectarian violence, jeopardizing Syriaâs chemical arsenal, and spreading Islamist extremism across the Arab world and beyond.