ARI SHAPIRO, HOST:
The White House says Syria may be preparing another chemical weapons attack on its citizens. Yesterday the White House warned President Bashar al-Assad that if he goes through with it, quote, "he and his military will pay a heavy price."
To help us understand why the White House issued that statement, we're joined by NPR Pentagon correspondent Tom Bowman. Hi, Tom.
TOM BOWMAN, BYLINE: Hey, Ari.
SHAPIRO: What has convinced the U.S. that another chemical weapons attack is in the works?
BOWMAN: Well, I'm told surveillance showed the hallmarks of chemical weapons activity at this Syrian air base. There were people and equipment around an aircraft hangar, and they detected a Syrian warplane, a MiG-23, being positioned and readied for chemical weapons. Now, facilities and aircraft at this Syrian base in that hangar were all linked to chemical weapons before. They were damaged back in April. You might remember when the U.S. fired dozens of Tomahawk missiles from two American destroyers in the Mediterranean. And that missile launch came after a chemical weapons attack from a Syrian aircraft at this base and that killed more than a hundred civilians, including many children. The Syrian regime, by the way, today denied any use of chemical weapons.
SHAPIRO: The White House issued this warning late last night in a statement from the press secretary, which does not seem like the usual way these things are done.
BOWMAN: You know, it was pretty unusual that they put this out that time of night and also before anything actually happened. And we have no sense at this point whether there's a possibility of another round of Tomahawk missile strikes or even whether this White House warning had any effect. Is there still activity at this airfield? Are they still, you know, working on this aircraft? Have they stopped? We - at this point, we just have no sense yet.
SHAPIRO: If the U.S. is confident that Syria is preparing chemical weapons for another attack, why not act now rather than issue a warning?
BOWMAN: Well, I'm told that first of all, you don't want to hit the chemical weapons. The U.S. is wary of actually striking a chemical weapons depot. That's a more complex target, I'm told. And the danger is a possibility of a - kind of a toxic cloud that could spread over civilian areas. It's always easier, they say, just to take out the airplanes.
SHAPIRO: That's NPR Pentagon correspondent Tom Bowman. Thank you.
BOWMAN: You're welcome, Ari.
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