(Bloomberg View) -- The recent air strikes by U.S., French and U.K. forces on Syrian chemical-weapons facilities were justified, appropriately scaled and efficiently executed. But Bashar al-Assad is still in power, Russia and Iran are still backing him, American-supported rebels are on the defensive, and peace talks through the United Nations are going nowhere.
Looking ahead, the U.S. and its allies face two questions: how to respond if the Syrian regime uses chemical weapons yet again, and how to ensure that the seven-year civil war doesn't descend into still greater chaos or engender more terrorist groups like the Islamic State.
Nobody should expect Assad to willingly refrain from new war crimes. On chemical weapons, he paused for almost a year after the U.S. bombed a Syrian airfield in response to an attack with sarin gas last spring, but he clearly isn't troubled about committing atrocities against his own people. Next time, if there is a next time, the U.S. and its allies should respond more severely.
What makes chemical weapons different? They are a cruel and terrible use of force, intended to spread terror more than to achieve specific military objectives. In addition, they've been outlawed for nearly a century -- so their use is a test of international resolve and a calculated boast of impunity.
Syria promised the U.S. back in 2013 that it would eliminate its chemical weapons, and is flouting that specific commitment. When regimes like the ones running Syria, Iran and North Korea make promises, they may not intend to keep them -- but they should understand that there will be consequences if they don't.
Responding to Syria's provocation is a compelling security interest for the U.S. and its allies. Toppling Assad, however, is not. The U.S. would be unwise to commit itself in Syria in anything like the way it did in Afghanistan and Iraq after the Sept. 11 attacks. Trump shouldn't withdraw the roughly 2,000 U.S. soldiers in Syria while the fight against the Islamic State is making progress -- but there should be no long-term American presence or attempts at nation-building.
The U.S. should continue to help its allies in the civil conflict -- the Kurdish YPG and the Syrian Democratic Forces -- with weapons, training and logistical support. But it shouldn't fight the war for them, or risk a major military conflict with Russian forces.
The Trump administration ought to focus instead on an admittedly tentative diplomatic solution -- one that might leave Assad in power for the time being. His puppet masters, Russia and Iran, are growing weary of sacrificing troops and money to prop him up, and may be willing to cut a deal that leaves anti-regime forces in control of parts of the nation.
To be sure, this is nobody's idea of a perfect outcome -- but it's better than the alternatives, and achievable at an affordable cost. It's the right goal for U.S. policy.
--Editors: Tobin Harshaw, Clive Crook.
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