"So far at least I don't think we've seen any examples among troops that are guarding these sites or any activities to suggest the chain of command is weakening," said Leonard Spector, a former senior nonproliferation official with the National Nuclear Security Administration. "I think what people are worried about is that the situation could become increasingly chaotic and the chain of command breaks down."
But if Syria's control of its arsenal collapses, he said, the consequences could be worse than in Libya. "It's a hundred times more serious in Syria," he said.
Andrew Shapiro, the assistant secretary of state for political-military affairs, said this month that the U.S. has helped recover 5,000 of Libya's portable anti-aircraft missiles, or about a quarter of the total.
Shapiro said many of the weapons that have not been accounted for were likely used in training, had broken down or were fired by rebels while fighting the regime. A substantial number probably remain in the hands of militias who defeated Libyan government forces and were often the first to "liberate" weapons sites, he said.
"Yet clearly we cannot rule out that some weapons may have leaked out of Libya," Shapiro told a non-proliferation group.
The U.S. plans to spend $40 million helping Libya secure and recover its stockpiles of portable anti-aircraft weapons, Shapiro said. The U.S. also will conduct an inventory of all Libyan weapons storage areas and has two mobile teams assigned to respond to the discovery of new portable missile caches, he added.
Royce and other Republican lawmakers said that if Syria's arsenals are threatened, the Obama administration should move faster than it did in Libya to secure unconventional weapons.
AP National Security Writer Robert Burns contributed to this report.
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