STEVE INSKEEP, HOST:
It's MORNING EDITION from NPR News. I'm Steve Inskeep.
DAVID GREENE, HOST:
And I 'm David Greene. Our understanding of the role chemical weapons are playing in Syria is no clearer today than it was a week ago. That's when President Obama said while there is evidence of chemical weapons used in the Syria, there is none pointing to who is responsible.
INSKEEP: On Sunday, a member of the U.N. Commission on Syria said there are indications that rebel forces were the ones who had used Sarin gas, not the Syrian government. Carla del Ponte said her conclusions were not final and the U.N. commission later emphasized that, insisting it had not reached any conclusions at all. Yesterday, White House spokesman Jay Carney said the administration is still treading cautiously in assigning blame.
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JAY CARNEY: We are highly skeptical of suggestions that the opposition could have or did use chemical weapons. We find it highly likely that any chemical weapon use that has taken place in Syria was done by the Assad regime.
INSKEEP: Listen to all the qualifications there. Any chemical weapons use, likely. The red line the president laid down to trigger great American involvement, possibly military, in the civil war still has not been crossed.
GREENE: To better understand all of this, we have Gary Samore on the line. He was the White House coordinator for arms control and weapons of mass destruction advising President Obama until late last year. He joins us from our member station WGBH in Boston. Mr. Samore, good morning. Thanks for joining us.
GARY SAMORE: Good morning.
GREENE: Can you tell me how hard it really is to determine who is responsible? Who has used chemical weapons in Syria, if anyone?
SAMORE: I think it's especially difficult when there are appears to be very small-scale tactical use because there's no forensic way to really determine exactly who used it. It would require some very sensitive intelligence information. And probably whether that information exists or not it's obviously difficult to make public.
GREENE: You say small-scale tactical use. Can you give us a sense of what kind of chemicals or chemical weapons we might be talking about? What's actually there and where are they?
SAMORE: Well, there's been a range of reports. The most serious accusation is that there was use of nerve gas, Sarin. But there also appears to be use of gasses like tear gas or chlorine, things that wouldn't necessarily kill people but would be irritants. In the same way that the police might try to flush criminals out of a building using tear gas, you could imagine on the battlefield there would be small-scale use against enemy forces that are located in a fortified position.
GREENE: So when we talk about chemical weapons, I mean, Sarin nerve gas, you're saying, is perhaps the most serious but there are types of tear gas that might not kill people that would still fall in this category of chemical weapons that President Obama has talked about being incredibly important in terms of a red line.
SAMORE: Well, President Obama was not specific about what chemical weapons he was referring to. Chemical weapons like tear gas are not prohibited by the Chemical Weapons Convention to presumably he was talking about mustard gas or nerve gas, which is prohibited by the Chemical Weapons Convention. Of course, Syria is not a party to that treaty and they're suspected of having a very large-scale chemical weapons program.
I think the most serious - if it's demonstrated that the Syrian forces use nerve gas, I think that would put the most pressure on the United States to do something in response, if that can be demonstrated.
GREENE: Demonstrated. We're still trying to sort our who might be using these weapons, if at all. But what would be the motivation on either side to use weapons like this?
SAMORE: Well, there may be some tactical advantage. As I said, you might be in a battlefield situation where there's no easy way to flush out enemy forces, so you might use chemical weapons as a way to force them to leave an area. That's one possibility. I also think there's a terror factor. According to some of the eyewitness accounts, it caused a lot of panic.
So one of the big concerns is that in the future, as this war continues, one side or the other might use chemical weapons against unprotected civilian populations. And that of course could lead to much larger casualties.
GREENE: How careful do you think the White House is being? I mean, you were inside this White House until fairly recently. Are they - do they know more than they're telling us?
SAMORE: It's hard for me to say that since I'm not in the White House anymore.
GREENE: I guess so.
SAMORE: I mean, I think the president obviously from the beginning has made it clear that he does not want to get dragged into this civil war for a variety of reasons. In part, because it's such a messy situation, in part because any really effective military intervention, either to stabilize the situation or to seize or destroy chemical weapons, would require a very large-scale military force. So he's seeking to avoid that. But I also think there's genuine uncertainty about what's going on, especially in the context of this small-scale use. Everyone seems to concede that the most likely scenario is that the Syrian government forces used chemical weapons, which could be a test to see how much they can get away with.
KENNEDY SCHOOL, HARVARD UNIVERSITY: And so, I think there will be some pressure on the White House to do something.
GREENE: All right, Gary Samore, thanks so much for joining us. We appreciate it.
UNIVERSITY: Thank you.
GREENE: He's the executive director of the Harvard Kennedy School's Belfer Center for Science and International Affairs. Transcript provided by NPR, Copyright NPR.