"I believe there was a chemical attack".
"I believe there was a chemical attack and we're looking for the evidence", he said.
"We will not know who did it". If the regime does allow an investigation, the inspectors will not be able to determine who launched a chemical attack, he said.
Mattis said the United States did not have any personnel on the ground in Douma during the attack and said time is of the essence to gather evidence.
There have been several similar attacks this year, he told lawmakers, but the US did not have troops in those locations because the U.S.is not engaged on the ground there.More news: Former US House Speaker To Promote Legalizing Marijuana
Asked if the U.S. was ready for an attack, Mattis replied that "We stand ready to provide military options if they're appropriate, as the president determined".
Warning that he was concerned that a United States strike might lead to an "out of control" escalation in the Syrian war, Mattis said that Washington was "committed to ending that war through the Geneva process through the United Nations orchestrated effort". "We're trying to stop the murder of innocent people, but on a strategic level, it's how do we stop this from escalating out of control?"
"Some things are simply inexcusable, beyond the pale and in the worst interest of not just the chemical weapons conventions but of civilization itself".
Several lawmakers grilled the Pentagon chief on the legal authorities the military has for action in Syria beyond the remit of its current mission, which is to work to destroy the Daesh. However, there have been "contrary impulses", he said, such as last year's USA missile strikes in Syria in response to a chemical attack and now recent discussions for another strike for the same reason.More news: Broncos 2018 preseason schedule released
Russian Federation on Thursday warned the U.S.to avoid any steps that could destabilize the situation there. "Get ready Russian Federation, because they will be coming, nice and new and 'smart!' You shouldn't be partners with a Gas Killing Animal who kills his people and enjoys it!" At a photo-taking session during a Pentagon meeting with his Dutch counterpart, Mattis was asked by a reporter whether he had seen enough evidence to blame the Syrian government.
"We're still assessing the intelligence ourselves, and our allies". "We're still working on this".
The Pentagon is now working under war powers granted in the aftermath of the September 11, 2001 attacks, even though operations across the Middle East have morphed broadly since those early days of seeking to destroy Al-Qaeda. Mr. Trump responded then by launching dozens of Navy cruise missiles at a Syrian airfield.
Mattis and Joint Chiefs Chairman Marine Gen. Joseph Dunford went before the House to testify on the fiscal 2019 defense budget as Capitol Hill buzzed with speculation about President Donald Trump's threats to attack Syria and possibly start a proxy war with Russian Federation.More news: Virginia woman accused of cutting man's head off