National Security Council aide Lieutenant Colonel Alexander Vindman listens as he testifies before the House Intelligence Committee on Capitol Hill in Washington, Tuesday, November 19, 2019, during a public impeachment hearing of President Donald Trump's efforts to tie U.S. aid to Ukraine to investigations of his political opponents. (AP Photo/Susan Walsh)
National Security Council aide Lt. Col. Alexander Vindman listens as he testifies before the House Intelligence Committee on Capitol Hill in Washington, Tuesday, Nov. 19, 2019, during a public impeachment hearing of President Donald Trump's efforts to tie U.S. aid for Ukraine to investigations of his political opponents. (AP Photo/Susan Walsh)