Final answer:
The Department of Defense was created to centralize the military branches and enhance national security efficiency. Post-Cold War, defense spending was reduced due to a decreased global threat, leading to a smaller armed forces size. The Office of the Director of National Intelligence improves intelligence agency functioning by enhancing communication and coordination.
Step-by-step explanation:
Creation of the Department of Defense and Downsizing of the Armed Forces:
The Department of Defense was created to bring together the U.S. Army and Navy within a single executive department. This centralization was part of the broader reorganization of U.S. military and security agencies under the National Security Act of 1947, which was aimed at streamlining government functions in the realm of national security. The act also established the National Security Council and the Central Intelligence Agency (CIA) to better coordinate intelligence and security efforts.
After the end of the Cold War and the dissolution of the Soviet Union, the perceived threat that had justified a large U.S. military presence decreased significantly. The discussions of a "Peace Dividend" emerged, suggesting that with a reduced threat of global conflict, the United States could afford to decrease defense spending and reallocate resources to other sectors. As a result, defense spending was reduced and the size of the armed forces decreased, aligning with a broader trend of post-Cold War demilitarization around the world.
The Office of the Director of National Intelligence (ODNI) was established to address the problems of disconnected and poorly cooperating intelligence agencies. The ODNI enhances the functioning of these agencies by facilitating strong communication and integration of efforts, thereby improving the overall effectiveness and responsiveness of the U.S. intelligence community.