The White House says President Donald Trump plans to address the nation at 11 a.m. Wednesday.

Trump faces one of the greatest tests of his presidency now that Iran has launched ballistic missiles at two Iraqi bases housing U.S. troops. It was Iran’s most brazen assault on America since the 1979 seizing of the U.S. Embassy in Tehran.

Iran’s missile strikes were in retaliation for last week’s American drone strike that killed Iran’s top general.

Trump huddled with his national security advisers to weigh a response. Top Senate Democrats are citing “deep concern” about the lack of information coming from the Trump administration about the Iran operation.