Mattis says 'there is no doubt' the Syrian government was responsible for chemical attack

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Defense Secretary James Mattis said Tuesday "there is no doubt" the Syrian government led by President Bashar Assad is responsible for chemical weapons last week that killed more than 100 people.

"This military action demonstrates that the United States will not passively stand by while Assad blithely ignores international law and employs chemical weapons he had declared destroyed," said Mattis, speaking at a briefing at the Pentagon. "The Syrian regime should think long and hard before it again acts so recklessly in violation of international law against the use of chemical weapons."

Last week, the U.S. military launched a missile strike against a Syrian government airfield in response to the chemical weapons used against civilians. Mattis said the U.S. was aware there were Russians at the Syrian base so the U.S. military "took appropriate actions to ensure no Russians were injured in the attack."

"We have gone back through and looked at all the evidence we can and it's very clear who planned this attack, who authorized this attack and who conducted this attack itself," said Mattis. But he stopped short of saying the Russians had advance notice of the chemical weapons attack.

The intent of the Syrian attack was "to stop the cycle of violence into an area," said the Defense secretary, adding that "even in World War II chemical weapons were not used on battlefields. Even in the Korean War, they were not used on battlefields."

The U.S. military policy in Syria hasn't changed and the priority remains the defeat of ISIS, or the Islamic State.

"ISIS represents a clear and present danger and immediate threat to Europe and ultimately a threat to the United States homeland," he said.

Army Gen. Joseph Votel, commander of the U.S. Central Command, provided detail at the presser on the Syrian strike at the Shayrat airfield and said the goal was to eliminate the chemical weapons capability, including aircraft, fuel and supplies that provided offensive military capacity for the Assad regime. "We did not deliberately target personnel in these strikes," Votel said.

According to Votel, the U.S. military targeted 59 locations at the Syrian government's Shayrat airfield and struck 57 of those targets. He said the U.S. believes the airfield was the launching point for last week's chemical attack.

Votel wouldn't comment on plans for any additional troop strength in the region. There are already believed to be at least 900 U.S. troops in Syria fighting ISIS, which includes the addition of around 400 troops added last month.

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