National Defense Authorization Act for Fiscal Year 2020 This bill authorizes FY2020 appropriations and sets forth policies for Department of Defense (DOD) programs and activities, including military personnel strengths and military construction. It does not provide budget authority, which is provided in subsequent appropriations legislation. The bill authorizes appropriations to DOD for Procurement, including aircraft, weapons and tracked combat vehicles, shipbuilding and conversion, missiles, and space procurement; Research, Development, Test, and Evaluation; Operation and Maintenance; Working Capital Funds; the Joint Urgent Operational Needs Fund; Chemical Agents and Munitions Destruction; Drug Interdiction and Counter-Drug Activities; the Defense Inspector General; the Defense Health Program; the Armed Forces Retirement Home; the Space Force; and Overseas Contingency Operations. The bill also authorizes the FY2020 personnel strengths for active duty and reserve forces 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; 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 activities.