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U.S. Says Chemical Weapons Used in Syria
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Kelsey Davenport and Daniel Horner

The U.S. intelligence community has “high confidence” that the Syrian regime used chemical weapons on a small scale against opposition forces multiple times over the past year, the White House said in a June 13 statement.

In the statement, Ben Rhodes, deputy national security adviser for strategic communications, said that physiological samples and reporting from multiple sources within Syria were consistent with exposure to chemical weapons, including the nerve agent sarin. The United States worked with its partners, allies, and individuals inside Syria to obtain and evaluate this information, he said.

Syria is not a member of the Chemical Weapons Convention (CWC) and has not disclosed the size and composition of its chemical weapons stockpiles. However, the U.S. intelligence community has estimated that the regime of Syrian President Bashar al-Assad possesses a large and complex chemical weapons program, including several types of nerve gases that can be delivered by missiles and bombs. After a Syrian government spokesman publicly acknowledged the existence of its chemical weapons last summer, President Barack Obama called the use or movement of chemical weapons within Syria a “redline” for U.S. action. (See ACT, September 2012.)

The United States has been evaluating claims of Syrian chemical weapons use for several months. In an April 25 letter to members of Congress, Miguel Roriguez, Obama’s director of legislative affairs said that the U.S. intelligence community had determined with “varying degrees of confidence” that the Assad regime had used chemical weapons against the Syrian population. More evidence was needed to confirm the use, the letter said, because there were doubts over the “chain of custody” of the evidence. (See ACT, May 2013.)

The June 13 statement described the evidence of use as “credible.”

Independent analysts have raised questions about the change in the U.S. assessment. In a June 18 interview, Amy Smithson, a senior fellow with the James Martin Center for Nonproliferation Studies, said the statement does not explain the increase in confidence since the April 25 letter or describe the chain of custody for the underlying evidence. Moreover, she said, the U.S. government has not provided evidence that rules out the possibility that rebel forces, who may want to incriminate the Assad regime, are responsible for the cases of small-scale use to date.

Jean Pascal Zanders, a former research fellow with the European Union Institute for Security Studies, said in a June presentation in Brussels that the United States, like France and the United Kingdom, had provided “[v]irtually no factual details on the nature and provenance of the samples [or] the laboratory results” that were the basis for its conclusions, “making independent assessments impossible.” It is not clear if, in its June 13 statement, the United States is drawing on the British and French evidence or its own analysis, he said in a June 19 interview.

Crossing Redlines

Rhodes said the intelligence community findings cross “clear” redlines and violate international norms. Accordingly, Obama changed his calculus on Syria and already increased nonlethal assistance to the opposition, he said. A number of “legal, financial, diplomatic and military responses” also are available, according to Rhodes.

In a follow-up press call June 13, Rhodes said that the U.S. aim is provide assistance that has “direct military purposes” and is “substantively different” from past aid. He would not confirm specifics of the assistance package. News outlets quoted unnamed administration officials as saying that small arms would be provided to the Syrian opposition forces.

Rhodes’ statement followed reports by the United Nations and France that each had concluded that chemical weapons were being used in Syria.

French Foreign Minister Laurent Fabius said June 4 that there was “no doubt” that Assad used sarin on several occasions. The French government tested samples smuggled out of Syria that confirmed the use of sarin, Fabius said.

The June 4 UN report said that there are “reasonable grounds” to believe that chemical weapons were used in Syria on two occasions in March and two in April but that it was not possible to identify the chemical agents or determine who used them.

After allegations that chemical weapons were used near Aleppo on March 19, Assad requested that the UN investigate the claims. Secretary-General Ban Ki-moon said that the UN would investigate in conjunction with the World Health Organization and the Organisation for the Prohibition of Chemical Weapons (OPCW), which oversees implementation of the CWC.

Syria has yet to allow investigators into the country due to a disagreement over the scope of the UN inquiry. Syria wants to restrict the investigation to the March 19 incident. Ban said the mission must be allowed to investigate “all the allegations” made by member states. (See ACT, May 2013.)

Syrian opposition forces have claimed that the Assad regime used chemical weapons in the March 19 incident. France and the United Kingdom have asked Ban to include other sites where the rebels have said the Assad regime used chemical weapons.

In the June 13 statement, Rhodes said that Washington briefed the head of the UN team, Åke Sellström, on its evidence and sent a letter to Ban informing him of the intelligence community’s evidence and assessments. The United States also is pushing for the UN team to have “immediate and unfettered access to conduct on-site investigations” in Syria, he said.

UN Probe Stalled

After Ban’s announcement, Sellström’s team assembled in Cyprus. But because of “the continued absence of an agreement” with the Syrian government on the terms of the team’s access, the team has left that country, UN spokesman John Ennis said in a June 19 e-mail to Arms Control Today.

The team “has been continuing to monitor developments and collect available information,” and Sellström has “visited capitals and has also been assessing other options for fact-finding activities outside of Syria, including in neighbouring countries,” Ennis said. In spite of the considerable time that has elapsed since the alleged March 19 incident, it is important for the team to be able to conduct an investigation in Syria because “[t]here are a range of possible on-site activities extending beyond the collection of environmental samples, which still could provide information on whether or not chemical weapons were used,” Ennis wrote.

Some evidence of chemical weapons use from the environment or from samples—for example, from the blood or urine of victims—is fleeting, but postmortem specimens of brain tissue will indicate the chemicals that caused death, Smithson said. Furthermore, she said, although environmental samples degrade, they do so along known chemical pathways, and gas chromatography-mass spectrometry can reliably identify these degradation by-products.

She cited the case of the 1988 gassing of the Iraqi town of Halabja by Saddam Hussein’s forces. More than four years later, she recalled, a team from Physicians for Human Rights collected samples that then were analyzed by the United Kingdom’s top chemical defense laboratory and found to contain degradation by-products of sarin and mustard gas.