DAVID GREENE, HOST:
It's MORNING EDITION, from NPR News. Good morning. I'm David Greene.
STEVE INSKEEP, HOST:
And I'm Steve Inskeep. On one level, this story is about nothing more than a bit of diplomatic jargon.
GREENE: On a deeper level, though, the stakes could not be higher. President Obama's administration told Syria that using chemical weapons against Syrian rebels is a red line.
INSKEEP: Diplomats use that term as a dire warning. The U.S. is putting its prestige on the line, saying that if Syria crosses that red line, it must expect the United States to deliver some unnamed, but severe response. It could even imply military action.
GREENE: Now, Israel has joined France and Britain in saying Syria used chemical weapons that would cross the line. But U.S. officials have been reluctant to accept the allegations.
INSKEEP: Raising questions about whether the red line is moving.
NPR's Michele Kelemen reports.
MICHELE KELEMEN, BYLINE: A top Israeli intelligence analyst was the latest to publicly weigh in on the debate about chemical weapons use in Syria. Brigadier General Itai Brun told a conference that he believes the Syrian government used a nerve agent, probably sarin gas, in its fight against rebel forces.
Secretary of State John Kerry - in Brussels for a NATO meeting - called Israeli Prime Minister Benjamin Netanyahu.
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SECRETARY JOHN KERRY: I think it's fair for me to say that he was not in a position to confirm that in the conversation that I had.
KELEMEN: Kerry says there will be follow-up.
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KERRY: But obviously, whatever allegations are made have to be thoroughly investigated, and it is appropriate to chase this one down and find out what's going on, no question about it.
KELEMEN: Britain and France had already asked the U.N. to investigate several instances of alleged chemical weapons use. And White House spokesman Jay Carney says the U.S. still wants to see Syria allow that U.N. team to work.
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JAY CARNEY: We support an investigation. We are monitoring this. And, you know, we have not come to the conclusion that there has been that use. But it is something that is of great concern to us, to our partners, and obviously unacceptable, as the president made clear.
KELEMEN: With key U.S. allies raising the possibility of chemical weapons use, the U.S. is in a tight spot, says Mona Yacoubian, a Syria expert at the Stimson Center.
MONA YACOUBIAN: The stakes are so high. President Obama - starting last August, and again when he visited Israel - laid out a very clear red line that if there was conclusive evidence of the use of chemical weapons, that this would, in his words, be a game changer.
KELEMEN: Yacoubian says the administration has reason to be cautious, making sure the intelligence is accurate and determining what sort of chemical agents might have been used. And then, she says, Washington will have to carefully weigh how to respond.
YACOUBIAN: The response to the use of chemical weapons is itself inordinately complicated, whether it's parachuting troops in, or using some kind of Special Forces to secure a site, whether it's bombing, whether it's using proxies. None of these options is without significant risk.
KELEMEN: But there are also risks of being too hesitant, says Andrew Tabler of the Washington Institute for Near East Policy. He says the Obama administration has been shifting its red lines, and Syrian President Bashar al-Assad is testing that.
ANDREW TABLER: Bashar is testing Obama and seeing what he can get away with. And what it seems to be - at least so far - is that, you know, he can go up the escalation chain from using fixed-wing aircraft to Scud missiles on his own population, over 200 thus far, and now approaching the use of chemical weapons.
KELEMEN: Tabler says the White House has been skeptical about the chemical weapons reports - not just because it's debating the accuracy of the intelligence.
TABLER: It's a policy decision from the president. The president doesn't want to intervene in Syria. I don't think he wants to intervene even in the case when chemical weapons are close to being used. And the United States will only get involved when it's absolutely sure that they have been used.
KELEMEN: President Obama refused to answer a question about this when he appeared before reporters alongside the emir of Qatar. But Syria was high on the agenda during those talks at the White House yesterday. Qatar has been actively arming Syrian rebels, and the U.S. wants to see that aid go to more moderate fighters.
Tabler says the U.S. will have a hard time shaping what's happening in Syria, though, as it continues what he calls a hands-off policy.
Michele Kelemen, NPR News, Washington. Transcript provided by NPR, Copyright NPR.