Obama’s chemistry test

Revelations out of Syria indicating the use of chemical weapons by President Bashar Assad’s regime are putting the credibility of President Obama to the test.

We open with a montage of the President saying Assad would cross a “red line” were he to resort to such weaponry in a civil war whose toll has topped 70,000 lives. Chemical attacks would be a “game changer” that would “change my calculus” about U.S. intervention, Obama has stated.

Another Obama iteration: “We will not tolerate the use of chemical weapons agains the Syrian people, or the transfer of those weapons to terrorists.”

We cut to Thursday, when Defense Secretary Chuck Hagel said, “our intelligence community does assess, with varying degrees of confidence, that the Syrian regime has used chemical weapons on a small scale in Syria, specifically, the chemical agent sarin.”

Syria is a dangerous thicket. The White House has recognized opposition forces trying to topple Assad and provided rebels with limited support, but it has refrained from supplying arms or imposing a no-fly zone. The battling is overshadowed by the involvement of Al Qaeda-inspired fighters.

Still, having so unequivocally and bluntly warned Assad not to cross his red line, Obama has no choice but to respond. He must do so — and be seen to do so — both judiciously and with strength.

Without tipping his hand, the President acknowledged as much on Friday, saying:

“Horrific as it is when mortars are being fired on civilians and people are being indiscriminately killed, to use potential weapons of mass destruction on civilian populations crosses another line with respect to international norms and international law. That is going to be a game changer.”

But he also said: “We have to act prudently. We have to make these assessments deliberately. But I think all of us . . . recognize how we cannot stand by and permit the systematic use of weapons like chemical weapons on civilian populations.”

Meanwhile, the White House said in a letter delivered to senators that “the chain of custody (of the deadly chemicals) is not clear, so we cannot confirm how the exposure occurred and under what conditions.”

This is murk where clarity is needed. Obama must place on the record the full evidence of Assad’s chemical use, be it proof beyond a reasonable doubt or something far less definitive.

In either case, the President must be fully convincing, in justifying potentially fateful action, up to and including use of the military, or in leaving no doubt that he stood down without breaking the word of the American commander in chief.

Obama’s chemistry test