Trump's new national security adviser a soldier-scholar

President Donald Trump has chosen as his national security adviser a soldier-scholar who fought in both Iraq wars.

Army Lt. Gen. H.R. McMaster also published an influential book that called out the U.S. government for "lies" that led to the Vietnam War.

The White House says McMaster will remain on active military duty while leading the National Security Council.

McMaster joins two retired generals — Defense Secretary Jim Mattis and Homeland Security Secretary John Kelly — already in Trump's inner circle, adding to the impression that the president prefers military men in top roles.

McMaster replaces retired Gen. Michael Flynn, who was fired last week after Trump determined that Flynn had misled Vice President Mike Pence about his discussion with Russia's ambassador to the U.S. during the presidential transition.