There is evidence that troops loyal to Syrian Bashar al-Assad have used chemical weapons, and U.S. lawmakers are urging President Obama to respond.
It's not that simple.
The military options range from one-off missile strikes on infrastructure linked to chemical weapons, to funneling more weapons in rebel hands, to to carving out no-fly zones, and even as far as putting 20,000 U.S. troops in Jordan for a ground invasion.
All carry risks. Invasion has its obvious drawbacks (which the U.S. learned in Iraq), and establishing a humanitarian area in the north by destroying Syrian air defenses and artillery may have the same effect.
"Once you set up a military no-fly zone or safe zone, you're on a slippery slope, mission creep and before you know it, you have boots on the ground," Bruce Riedel, a former CIA analyst and Middle East expert at the Brookings Institution, told Reuters. "Or you end up like Libya where you don't really have a control mechanism for the end-game, should you end up with chaos."
The CIA is already working with elite counterterrorism units in Iraq, training rebels in Jordan on how to identify and safeguard chemical weapons, funneling weapons to Syrian rebels from southern Turkey, feeding intelligence to moderate rebels, and even scoping out targets for potential drone strikes.
But last week U.S. Defense Secretary Chuck Hagel warned that "no international or regional consensus on supporting armed intervention now exists."
Syria's neighbors — Israel, Iraq, Turkey, and Jordan— are reluctant, and the West has become increasingly concerned about the increasing power of al-Qaeda-linked Syrian rebels.
The U.K. is pushing for increased support for the opposition "to make sure we are supporting people with good motives who want a good outcome, to put pressure on that regime so we can bring it to an end."
Experts say the only proportional military responseto limited chemical weapons use would be striking units responsible — akin to Israel's strike on a suspected weapons convoy bound for Hezbollah militias in Lebanon.
"[A one-off strike] would demonstrate to Assad that there is a cost to using these weapons — the problem so far is that there's been no cost to the regime from their actions," Jeffrey White, a former senior official at the Pentagon's Defense Intelligence Agency and current defense fellow at the Washington Institute For Near East Policy, told Reuters.
Even a one-off strike would surely anger Russia and Iraq, and there may be some form of retaliation on U.S. interests in the region from Syria, Iran, or Hezbollah.
So even though Obama received criticism for moving his "red line," Century Foundation fellow Stephen Schlesinger may be right:
"A president has a right to change his position on a matter like this given the awful consequences of intervention."
SEE ALSO: This Is What Happens To Someone Hit By The Nerve Toxin Allegedly Used By Assad
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