Defense Secretary Jim Mattis pledged on Thursday to notify congressional leaders before any attack against the Syrian regime of Bashar Assad.
Testifying before the House Armed Services Committee on Thursday, Mattis said he believes the regime used chemical weapons in a recent attack, but largely avoided discussing the likelihood the U.S. would launch a retaliatory attack.
"We'll keep open lines of communication. There will be notification to the leadership, of course, prior to the attack," Mattis told lawmakers. "But we'll give a full report to the Congress itself probably as rapidly as possible."
"I believe there was a chemical attack, and we're looking for the actual evidence," Mattis added, noting the U.S. is seeking to get international inspectors on the ground to make that determination.
Despite Mattis' unwillingness to discuss potential operations, President Donald Trump appeared to telegraph forthcoming strike against the Syrian regime Wednesday, writing on Twitter that missiles "will be coming, nice new and 'smart!'"
On Thursday, Trump insisted on Twitter that he hadn't abandoned the element of surprise, tweeting that an attack in Syria could happen "very soon or not so soon at all!"
Pressed on the strategy toward the Assad regime and the long-running Syrian civil war, Mattis said the administration's policy is simply to defeat the Islamic State in Syria and pursue a diplomatic end to the civil war there.
"Both the last administration and this one made very clear that our role in Syria is the defeat of ISIS," Mattis explained. "We are not going to engage in the civil war itself."
But, referencing a missile strike against the Assad regime just over a year ago by the Trump administration in response to a gas attack, Mattis several times called the latest reported chemical attack "inexcusable."
"Some things are simply inexcusable, beyond the pale and in the worst interests of not just the chemical weapons convention, but of civilization itself," he said.