It started with just 20 words, intended to keep Barack Obama out of a war. The tens of thousands dying in Syria was a global tragedy, he told reporters a year ago, when the worst horrors were still months away, but as commander in chief he had to focus on American strategic interests and could not intervene in every humanitarian tragedy around the world.
Then he offered his one caveat. “A red line for us,” he said, “is we start seeing a whole bunch of chemical weapons moving around or being utilized.”
A year later, a president famously inclined to disentangle himself from the Middle East now finds himself trapped by that seemingly simple declaration. To do nothing in the face of images of children killed by poison gas would cripple his credibility in the last three years of his presidency. As Secretary of State John Kerry said on Friday, in making the case for a military strike, “it matters if nothing is done,” not least because of the signal it sends to the Iranians, the North Koreans and others who are measuring Mr. Obama’s willingness to enforce other red lines on far worse weapons. For those countries, it remains an open question — even after the drone strikes against terrorists and cyberattacks on nuclear facilities — if a president elected to get America out of wars is willing to take the huge risks of enforcing his lines in the sand.