An internal government memo leaked to the New York Times today confirmed what some had speculated about for months: Syrian President Bashar al-Assad's troops have used chemical weapons against rebel forces in the nation's civil war.

According to the internal memorandum, intelligence agencies have 'high confidence' in their assessment, and estimate that between 100 and 150 people have died to date from chemical weapons attacks. The memorandum goes on to say that the conclusion is based on a variety of intelligence.

Two months ago, Obama said there was evidence proving that sarin nerve gas had been deployed in Syria, according to the Times, though there were still questions about who had used it against whom. Today's memo, which comes more than a week after France said it had "no doubt the [Assad] regime and its accomplices" had used gas, puts those questions to rest.

The query now at the feet of the Obama administration is how to respond to this news. Ben Rhodes, deputy national security adviser to the president and novelist manqué, said in a statement "the use of chemical weapons violates international norms and crosses clear red lines." Presaging that declaration, Obama himself said at the end of April that the Syrian government using chemical weapons would force him "to rethink the range of options available to us."

Thus far President Obama has been assiduous about not getting too caught up in Syria's upheaval, but today's revelation may finally be what moves his hand.

Republican Senators John McCain and Lindsey Graham this afternoon renewed pleas for a no-fly zone and air strikes on Syrian landing strips—though they stopped short of calling for American military ground troops.

"The goal is to end the war. And the only way this war is going to end quickly and on our terms is to neutralize the air assets that Assad enjoys," Graham told Politico. "We can crater the runways. There are four air bases he uses. We can stop the planes from flying. We can shoot planes down without having one boot on the ground."

[Image via AP]