SHARE THIS VIDEO —

Defense Sec. Austin apologizes for keeping his hospitalization secret from Biden and the public

At a news conference, Defense Secretary Lloyd Austin said the United States will "take all necessary actions" to defend itself after the drone attack that killed three U.S. soldiers. And Austin said he was "deeply sorry" for keeping his recent prostate cancer treatment secret from the president and the public, saying he had "apologized directly to President Biden." NBC News’ chief White House correspondent Peter Alexander reports.