WASHINGTON, DC - JULY 06: U.S. President Barack Obama arrives with Secretary of Defense Ashton Carter (R) before delivering a statement from the Roosevelt Room at the White House on the deployment of U.S. troops in Afghanistan July 6, 2016 in Washington, DC. Obama said more U.S. troops will remain in Afghanistan than he originally planned, leaving 8,400 U.S. troops rather than the intended 5,000. (Photo by Win McNamee/Getty Images)

WASHINGTON, DC - JULY 06: Journalists wait for U.S. President Barack Obama to deliver a statement from the Roosevelt Room at the White House on the deployment of U.S. troops in Afghanistan July 6, 2016 in Washington, DC. Obama said more U.S. troops will remain in Afghanistan than he originally planned, leaving 8,400 U.S. troops rather than the intended 5,000. (Photo by Win McNamee/Getty Images)

US President Barack Obama delivers a statement on Afghanistan with Defense Secretary Ashton Carter (L) and the Chairman of the Joint Chiefs of Staff Gen. Joseph Dunford at the White House in Washington, DC, on July 6, 2016. Obama announced that 8,400 US troops will remain in Afghanistan into 2017 in light of the still "precarious" security situation in the war-ravaged country. / AFP PHOTO / NICHOLAS KAMMNICHOLAS KAMM/AFP/Getty Images

WASHINGTON, DC - JULY 06: U.S. Speaker of the House Rep. Paul Ryan (R-WI) speaks during a press briefing after a House Republican Conference meeting July 6, 2016 at the headquarters of Republican National Committee in Washington, DC. Speaker Ryan spoke on FBI's decision of not to recommend criminal charges against Hillary Clinton for using a private email server during her time as secretary of state. (Photo by Alex Wong/Getty Images)

WASHINGTON, DC - JULY 06: U.S. Speaker of the House Rep. Paul Ryan (R-WI) (R) looks on as House Republican Whip Rep. Steve Scalise (R-LA) (L) speaks during a press briefing after a House Republican Conference meeting July 6, 2016 at the headquarters of Republican National Committee in Washington, DC. Speaker Ryan spoke on FBI's decision of not to recommend criminal charges against Hillary Clinton for using a private email server during her time as secretary of state. (Photo by Alex Wong/Getty Images)

WASHINGTON, DC - JULY 06: U.S. Speaker of the House Rep. Paul Ryan (R-WI) holds up a copy of the U.S. Constitution during a press briefing after a House Republican Conference meeting July 6, 2016 at the headquarters of Republican National Committee in Washington, DC. Speaker Ryan spoke on FBI's decision of not to recommend criminal charges against Hillary Clinton for using a private email server during her time as secretary of state. (Photo by Alex Wong/Getty Images)

WASHINGTON, DC - JULY 06: U.S. President Barack Obama, flanked by Secretary of Defense Ashton Carter and Chairman of the Joint Chiefs of Staff Gen. Joseph Dunford (R), delivers a statement from the Roosevelt Room at the White House on the deployment of U.S. troops in Afghanistan July 6, 2016 in Washington, DC. Obama said more U.S. troops will remain in Afghanistan than he originally planned, leaving 8,400 U.S. troops rather than the intended 5,000. (Photo by Win McNamee/Getty Images)

WASHINGTON, DC - JULY 06: U.S. President Barack Obama delivers a statement from the Roosevelt Room at the White House on the deployment of U.S. troops in Afghanistan July 6, 2016 in Washington, DC. Obama said more U.S. troops will remain in Afghanistan than he originally planned, leaving 8,400 U.S. troops rather than the intended 5,000. (Photo by Win McNamee/Getty Images)