Once more, negotiators are assembling to try to end the Syrian bloodshed. Yet as they gather in Vienna for multilateral talks Saturday, the political obstacles they face are enormous: Who will represent the armed groups, and which groups will be excluded? Who should decide the fate of President Bashar Assad, and when? Can Syria's territorial integrity be maintained, or must the country end up a series of fiefdoms? Can the Iranians and Saudis be made to cooperate?
These and similar imponderables are likely to consume the negotiators for a long time. Meanwhile, the slaughter continues, with an estimated quarter of a million dead, 4 million refugees (many headed to Europe), an additional 6 million to 8 million displaced within the country, hundreds of thousands of civilians besieged, thousands more in detention, and suffering as far as the eye can see.
So far the international community's answer to this endless misery has been to say: We'll arrange peace, and then everything will be fine. But the Syrian people have been paying the price of the inadequacy of that answer for nearly five years.
The depressing reality is that the odds of achieving a peace accord anytime soon are remote. Even Russia's military engagement in Syria — ostensibly to fight Islamic State but mainly to bolster Assad — doesn't appear to be the game changer that President Vladimir Putin had hoped.
Instead of betting all on the elusive goal of peace, why not make a central point of the talks the protection of civilians? Ending the war is not the only way to safeguard the men, women and children who want no part in the conflict.
It is possible for combatants to continue shooting at each other but for noncombatants to be spared. That's what the Geneva Conventions and international humanitarian law are largely about.
What has made this war so deadly is that so many parties to it — and foremost Assad's forces — have pursued a war strategy centered on flouting the Geneva Conventions.
Many armed groups — most notably Islamic State but also other extremist groups such as Al Nusra Front and Ahrar al Sham — have been responsible for atrocities against civilians. But by far the largest cause of Syrian civilian deaths — and the resulting flight of refugees — is the Assad government's decision to treat as military targets the civilians and civilian institutions in areas seized by the opposition.
The Syrian military has bombed and shelled hospitals, schools, bakeries, markets — any place that civilians live or congregate. The apparent aim is to depopulate areas where opposition forces operate and send a lesson to others that this will happen to their neighborhoods, too, if opposition forces overrun them.
The cost of that ruthless, and illegal, strategy is paid not simply in Syrian lives lost and Syrian families displaced. It is also an impediment to peace.
When fighters see their families attacked, their homes destroyed, their neighborhoods pulverized, it radicalizes them. Finding common ground with your enemy is hard enough when it is shooting at your soldiers. A regime that slaughters your family generates a special kind of hatred that makes that prospect all the more elusive.
There's no harm in trying to negotiate a lasting peace in Vienna; there's just little reason to believe that these talks will be any more fruitful than their many predecessors. The negotiators should therefore also focus on possible points of agreement that could make a real and immediate difference for Syria's remaining civilian population.
If those gathered around the table in Vienna don't have the power to stop the violence once and for all, they do have the clout to set up a mechanism for documenting and censuring war crimes. The Assad government depends increasingly for its survival on Russia and Iran. The United States, the European Union, Turkey and the Persian Gulf states have enormous influence over the various elements of the opposition.
Presumably no one in Vienna would openly countenance the targeting of civilians. But none of the negotiators are actively pressing for an end to this practice by their allies. The Vienna talks could matter a great deal if the assembled parties resolved to stop paying mere lip service to the Geneva Conventions and start insisting on respect for them by all forces fighting in Syria.
Kenneth Roth is executive director of Human Rights Watch.
Follow him on Twitter: @KenRoth.