National Defense Authorization Act for Fiscal Year 2020 This bill authorizes FY2020 appropriations and sets forth policies regarding the military activities of the Department of Defense (DOD), military construction, and the national security programs of the Department of Energy (DOE). It does not provide budget authority, which is provided in subsequent appropriations legislation. The bill authorizes appropriations to DOD for (1) Procurement, including helicopters, weapons, aircraft, vessels, shipbuilding and conversion, and missiles; (2) Research, Development, Test, and Evaluation; and (3) Operation and Maintenance. The bill also authorizes the FY2020 personnel strengths for active duty and reserve forces. The bill authorizes appropriations and sets forth policies regarding military personnel; compensation and other personnel benefits; health care; acquisition policy and management; DOD organization and management; civilian personnel matters; matters relating to foreign nations; cooperative threat reduction; working capital funds; chemical agents and munitions destruction; drug interdiction and counter-drug activities; the Defense Inspector General; the Defense Health Program; the National Defense Sealift Fund; Overseas Contingency Operations; strategic programs, cyber, and intelligence matters; and the establishment of the Space Force within the Air Force. The bill authorizes appropriations and sets forth policies regarding military construction for the Army, Navy, Air Force, defense agencies, the North Atlantic Treaty Organization Security Investment Program, and Guard and Reserve Forces facilities. The bill authorizes appropriations for base realignment and closure (BRAC) activities and prohibits an additional BRAC round. The bill also authorizes appropriations and sets forth policies for DOE national security programs, including the National Nuclear Security Administration, and the Defense Nuclear Facilities Safety Board; the Maritime Administration; perfluoroalkyl and polyfluoroalkyl substances (PFAS) release disclosure, detection, and safe drinking water assistance; sanctions with respect to foreign traffickers of illicit synthetic opioids; sanctions with respect to North Korea; matters relating to elements of the intelligence community; election matters; and security clearances.