According to Secretary of Defense Chuck Hagel, the United States now believes “with some degree of varying confidence” that sarin gas specifically was the agent utilized in Syria. Secretary of State John Kerry went further, telling to the Associated Press that the Syrian government launched two chemical attacks within the country.
The White House also sent a letter echoing Hagel’s assessment to Sen. Carl Levin (D-MI) and Sen. John McCain (R-AZ) in response to a letter the two had previously sent. According to the letter, the U.S. is unable to determine precisely who used the deadly gas at this time, but believes the Syrian government is the culprit as the regime still maintains control over its weapon stockpiles.
Hagel’s statement — given to reporters while traveling in the Middle East — comes after several days of such claims being made among U.S. allies, including France, the United Kingdom, Israel and Qatar. Until today’s revelation, the United States maintained that there wasn’t enough evidence to make that determination with certainty. According to the letter to Congress, the U.S. assessment is based on “physiological evidence,” setting it apart from the photographic evidence the British and French used to come to their conclusion. The White House was also sure to point out that the chain of custody of that evidence is unclear, making the exact details of how the sarin exposure occurred and under what conditions unclear.
Syrian President Bashar al-Assad’s stockpile of chemical weapons has been a major concern to Western and Gulf states monitoring the conflict in Syria, who have feared both their use against civilians and rebels alike. Accusations in March flew from each side of the Syrian conflict, claiming that the other had used chemical weapons. These claims prompted the launch of a United Nations investigation, which the Syrian government has so far stymied.
One of the reasons the Obama administration has placed such importance on the use of chemical weapons in the Syrian war is their special status in international law. After witnessing the widespread use of choking gases like chlorine and blistering agents like mustard gas in World War I, the international community codified rules prohibiting the use of chemical weapons. The Protocol was flouted during World War II (particularly by Japanese and Italian forces), but it has held more force in recent years. The only confirmed uses of the sorts of nerve gases allegedly used in Syria — easily dispersed, rapidly acting poisons that have become the most prevalent form of chemical weapon — were by Saddam Hussein’s Iraq during the Iran-Iraq War and against Kurdish civilians in the north.
What remains to be seen is precisely what action the United States will take in response to this revelation. The use of chemical weapons has long been a declared “red-line,” an action that would prompt the United States to intervene more directly in Syria. “I want to make it absolutely clear to Assad and those under his command — the world is watching,” Obama said in December. “The use of chemical weapons is and would be totally unacceptable. And if you make the tragic mistake of using these weapons, there will be consequences and you will be held accountable.”
Wired’s Danger Room blog reports that the “physiological samples” mentioned in the White House letter are blood samples, taken from multiple people, that tested positive for sarin.