U.S. military history spans from the colonial period to the present, marked by significant conflicts such as the American Revolutionary War, the Civil War, and both World Wars. The military has evolved in response to changing technologies and strategies, influencing the nation’s development and global standing. Key events include the establishment of the U.S. Army in 1775 and the creation of the Department of Defense in 1947. The military has played a crucial role in shaping U.S. foreign policy, participating in various conflicts like the Vietnam War and the Gulf War, reflecting the nation’s commitment to national security and international alliances.