Is President Obama falling into a trap of his own making?
The Obama administration has assiduously avoid intervening in Syria, where more than two years of conflict has left upwards of 100,000 people dead.
Even against that backdrop of so much suffering, there's a case to be made that the use of chemical weapons is an entirely different matter.
"International peace and security depend on certain taboos that are easily recognized when they are broken," says Ian Lustick, a University of Pennsylvania political scientist. "It can be more important for an intervention to take place because nuclear or chemical or biological weapons are used, as opposed to just measuring how many people are killed."
Obama said Friday he hasn't decided on launching a military response against President Bashar Assad's regime in Syria. But having warned that use of chemical weapons would cross a "red line," Obama may feel compelled to do so.
"We cannot accept a world where women and children and innocent civilians are gassed on a terrible scale," Obama said.
Airstrikes may or may not put an end to the use of chemical weapons in Syria. But they certainly won't end the conflict there.
"This is a potentially game-changing move by the Obama administration that's very risky for his overall foreign policy," says Brian Katulis, a senior fellow at the Center for American Progress, a liberal-leaning think tank. "It can risk getting him pulled in, in ways he himself doesn't know."
Here is the danger: If Obama acts now, he will have himself crossed a line that will make it difficult for the U.S. to retreat back to the sidelines.
Obama says his goal will not be to end the Assad regime or even tilt conditions on the ground. But it will be difficult to sustain an argument that chemical weapons are an issue entirely separate from the broader conflict — especially if and when Syria retaliates against the U.S. or neighboring allies such as Lebanon or Israel.
"Sometimes credibility is too simply evoked as how you're perceived, but at a certain point you do get trapped by your promises," says David Ekbladh, a historian and expert on U.S. foreign relations at Tufts University. "This is one of those times,"
A Wary Nation
An NBC News poll released Friday found that 79 percent of Americans believe Obama should win approval from Congress before taking military action in Syria.
Given the low esteem in which Congress is generally held these days, such a strong desire for congressional signoff is a clear indication of the public's wariness of the U.S. getting involved in Syria.
"The shadow of Iraq still hangs heavy in the minds of many people," Katulis says. "On all national security questions, especially in the Middle East, the public is just tired. It's done."
If the bombing campaign goes well — if there aren't any American casualties and Assad capitulates in some fashion rather than retaliating — public opinion will turn around quickly, Katulis argues.
But he points out that there are many risks involved in this type of operation. He warns that even the attempt to respond to the use of chemical weapons could backfire, with hard-liners in the Assad regime further emboldened to use any tools they have to hand.
"I'm skeptical that one strike, or set of strikes, will be the end of it," says Jeremi Suri, an international historian and author of Liberty's Surest Guardian: American Nation-Building From the Founders to Obama. "The negative scenario if we do this is that Syria does something that involves Lebanon and Israel."
The Case For Responding
Suri argues that not responding with force at this point would essentially give a green light not just to Assad but to other dictators, who would conclude that they could use chemical weapons with impunity.
"The president and his closest advisers really don't want to get involved in Syria — their bias is against this," he says. "But the president feels that the use of chemical weapons crosses a line that is really dangerous."
Over the past 20 years, the U.S. has on several occasion used cruise missiles or other types of air strikes to respond to challenges, without getting more deeply embroiled in conflicts in any immediate or lasting way.
Recall the strikes against Iraq in 1998 in the wake of a threat against former President George H.W. Bush, for example, or following the bombings of U.S. embassies in Kenya and Tanzania that same year.
"This is not President Obama saying we're going to have the third big war after Iraq and Afghanistan," says Alan Kuperman, a professor of public affairs at the University of Texas who has written about humanitarian interventions.
"He's being very, very clear about a very discreet strike that will uphold a norm, which will also help Obama by restoring his credibility," Kuperman says.
If there is conclusive proof that the Assad regime ordered a chemical weapons attack, that justifies a military response by the U.S., Kuperman says.
"Even before their use in World War I, people recognized that chemical weapons have a speed and horror that's different from someone being shot," says Ekbladh, the Tufts historian. "There's a difference between killing people with artillery shells and using chemical weapons as a blanket to smother 1,400 people quickly."
But Ekbladh says you can practically read the frustration on Obama's face in recent days. He appears to know that "tit always leads to tat," as Ekbladh says.
In a situation as muddled as Syria, separating out the issue of chemical weapons use from the rest of the conflict will be almost impossible. Once the bombing starts, Obama may feel, as Abraham Lincoln did during the Civil War, that he is unable to control events, but rather risks being controlled by them.
"It seems to me that we are going to be engaged in a strike because he had a lack of wisdom to avoid laying down a red line," says Rajan Menon, a political scientist at City College of New York. "This is the second time the red line has been crossed, so now he's boxed in."