Defense Secretary James N. Mattis greets British Defense Secretary Gavin Williamson at the Pentagon on Thursday, Feb. 1, 2018. Mattis issued a stern warning Friday to the embattled Syrian regime that the United States is investigating claims of its recent use of banned chemical weapons. (Amber I. Smith/U.S. Army)
WASHINGTON — Defense Secretary Jim Mattis issued a stern warning Friday to the embattled Syrian regime that the United States is investigating claims of its recent use of banned chemical weapons.
“You all have seen how we reacted to that [last year], so they would be ill-advised to go back to violating the chemical conventions,” Mattis told reporters at the Pentagon, referencing a U.S. bombing raid of a Syrian air base in April in response to Syrian President Bashar Assad’s sarin gas attack against civilians earlier that same month.
The United States has not seen direct evidence that Assad has recently used sarin gas, Mattis said, though various non-government organizations and rebel groups fighting Syrian government forces have alleged the regime continues to use chemical weapons in the nearly 7-year-old civil war.
Assad’s past use of the sarin, a banned highly toxic nerve agent, gives the United States “reason to suspect” those groups’ claims are accurate.
“We’re not refuting them,” Mattis said. “We are looking for evidence of it, since clearly we are dealing with the Assad regime, which has used denial and deceit to hide their outlaw actions.”
Last year, President Donald Trump ordered the Navy to launch 59 Tomahawk cruise missiles into Syria’s Shayrat air base on April 6, just two days after Assad’s sarin gas attack on civilians. The U.S. attack destroyed more than 20 Syrian warplanes and killed at least seven Syrian troops, U.S. and Syrian officials said at the time.
Assad has repeatedly denied his military’s involvement in the sarin attack, but groups including the United Nations and The Hague-based Organisation for the Prohibition of Chemical Weapons concluded his regime was responsible.
In 2013, Assad reached an agreement with former President Barack Obama to turn over his chemical weapons to international bodies and join the Chemical Weapons Convention, an international agreement that prohibits the development, production, acquisition, stockpiling, retention or transfer of chemical weapons.
But U.S. officials have said Assad has held on to his chemical weapons, and the State Department on Thursday accused Syria’s regime of developing new weapons to deliver chemicals including chlorine and sarin.
The latest allegation of Syria using chemical weapons came from the White Helmets group, a volunteer battlefield rescue organization, who on social media accused Assad’s regime of launching a chlorine gas attack Thursday in rebel-held Eastern Ghouta, near Syria’s capital of Damascus. The allegation has not been confirmed by monitoring groups, including Human Rights Watch.
Mattis said Syria has likely used weaponized chlorine gas repeatedly. Though illegal to use under international law, chlorine gas attacks are not as severe or as concerning as sarin attacks, he said.
Chlorine, a legal chemical around the world, is classified as an irritant and is rarely deadly. People exposed to even a small amount of sarin can be killed in minutes, according to the national Centers for Disease Control and Prevention.
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