national security

Senate Majority Leader Mitch McConnell of Ky., departs the chamber on Capitol Hill in Washington, Monday, Jan. 27, 2020, after the impeachment trial of President Donald Trump on charges of abuse of power and obstruction of Congress ended for the day. (AP Photo/Patrick Semansky)

This artist sketch depicts Senate Majority Leader Mitch McConnell, R-Ky., left, and Senate Minority Leader Chuck Schumer, D-N.Y., right, listening to defense arguments in the impeachment trial of President Donald Trump on charges of abuse of power and obstruction of Congress, at the Capitol in Washington, Monday, Jan. 27, 2020. (Dana Verkouteren via AP)

FILE - In this July 31, 2019 file photo, then National security adviser John Bolton speaks to media at the White House in Washington. Bolton says he's 'prepared to testify' in Senate impeachment trial if subpoenaed (AP Photo/Carolyn Kaster)

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President Donald Trump speaks during an "Evangelicals for Trump Coalition Launch" at King Jesus International Ministry, Friday, Jan. 3, 2020, in Miami. (AP Photo/ Evan Vucci)

From left House Speaker Nancy Pelosi, Chairwoman of the House Financial Services Committee Maxine Waters, D-Calif., Chairman of the House Foreign Affairs Committee Eliot Engel, D-N.Y., House Judiciary Committee Chairman Jerrold Nadler, D-N.Y., Chairwoman of the House Committee on Oversight and Reform Carolyn Maloney, D-N.Y., House Ways and Means Chairman Richard Neal and Chairman of the House Permanent Select Committee on Intelligence Adam Schiff, D-Calif., unveil articles of impeachment against President Donald Trump, during a news conference on Capitol Hill in Washington, Tuesday, Dec. 10, 2019.(AP Photo/Susan Walsh)

This undated photo provided by West Midlands Police shows Usman Khan. UK counterterrorism police are searching for clues into an attack that left two people dead and three injured near London Bridge. Police said Saturday, Nov. 30, 2019, Khan, who was imprisoned six years for terrorism offenses before his release last year stabbed several people in London on Friday, Nov. 29, before being tackled by members of the public and shot dead by officers on the London Bridge. (West Midlands Police via AP)

Former White House national security aide Fiona Hill, and David Holmes, a U.S. diplomat in Ukraine, back right, walk to their seats to testify before the House Intelligence Committee on Capitol Hill in Washington, Thursday, Nov. 21, 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/Manuel Balce Ceneta)

National Security Council aide Lt. Col. Alexander Vindman 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)

Career Foreign Service officer George Kent and top U.S. diplomat in Ukraine William Taylor, right, are sworn in to testify during the first public impeachment hearing of the House Intelligence Committee on Capitol Hill, Wednesday Nov. 13, 2019 in Washington.(AP Photo/Andrew Harnik)