UNITED NATIONS — Despite months of laboratory testing and scrutiny by top U.S. scientists, the Obama administration’s case for arming Syria’s rebels rests on unverifiable claims that the Syrian government used chemical weapons against its own people, according to diplomats and experts.
The United States, Britain and France have supplied the United Nations with a trove of evidence, including multiple blood, tissue and soil samples, that U.S. officials say proves that Syrian troops used the nerve agent sarin on the battlefield. But the nature of the physical evidence — as well as the secrecy over how it was collected and analyzed — has opened the administration to criticism by independent experts, who say there is no reliable way to assess its authenticity.
Violence flared in Aleppo and Damascus on Thursday, as pro-government troops went on offense against rebels.
A look at the Syrian uprising nearly two years later. Thousands of Syrians have died and President Bashar al-Assad remains in power, despite numerous calls by the international community for him to step down.
The technical data presented by the three Western powers is of limited value to U.N. inspectors trying to determine whether
Syria’s combatants used chemical weapons during the country’s 25-month-old conflict. Under the United Nations’ terms of reference, only evidence personally collected by its inspectors can be used to fashion a final judgment.
But no inspectors have been allowed inside Syria, so Western governments have relied on physical evidence smuggled out of the country by rebels or intelligence operatives. Precisely who acquired the evidence and what methods were used to guard against tampering may be unknowable, according to experts experienced at investigating chemical weapons claims.
“You can try your best to control the analysis, but analysis at a distance is always uncertain,” said David Kay, a former U.N. weapons inspector who led the U.S. search for weapons of mass destruction in Iraq after the 2003 invasion. “You’d be an idiot if you didn’t approach this thing with a bit of caution.”
U.S. defends analysis
The Obama administration announced last week that it was expanding military support to the rebels after concluding with “high confidence” that Syria’s government had used chemical weapons on a small scale, according to a White House statement. President Obama had warned Syrian leader Bashar al-Assad in August that any use of his chemical arsenal would cross a “red line” and draw a strong U.S. response.
The first report of sarin attacks trickled out of Syria in January, and the administration initially played it down. By March, Britain and France reported that they had received evidence of such attacks and, in a joint letter, asked the United Nations to investigate rebel claims of chemical weapons use by Syrian authorities. Britain also provided soil samples it had tested. The Obama administration continued to collect and analyze data for three more months before reaching the same conclusion.
The number of deaths from poison gas was estimated at 100 to 150 — a relatively small number in a conflict that has killed more than 90,000 people. But the “red line” declaration had committed the administration — which had been resisting pressure to militarily intervene — to act. At the same time, the president’s language handed the Syrian opposition a powerful incentive to fabricate evidence, some weapons experts noted.