Men and women of the U.S. Armed Forces have served the nation from the Revolutionary War through the War Between the States and the War on Terrorism, answering the call to duty from Yorktown and Gettysburg to Quang Tri Province and Baghdad, and many gave their lives in defense of freedom. In the 20th and 21st centuries, that service included World War I, which began on July 28, 1914, lasted more than four years, caused more than 37 million military casualties and more than 10 million civilian deaths, ended with the Armistice on Nov. 11, 1918, and cost more than $186 billion; World War II, which began in 1939, spread across Europe, North Africa, and the Pacific, ended with Germany's surrender on May 7, 1945, and Japan's on Sept. 2, 1945, introduced the atomic bomb and the long range rocket, cost the United States an estimated $341 billion, caused 292,131 U.S. battle deaths and 115,187 deaths from other causes, and contributed to an estimated 60 million deaths worldwide, including Holocaust victims; the Korean War, America's first ideological conflict, in which more than 16 million service members worldwide took part, North Korea invaded South Korea on June 25, 1950, cease fire talks began on July 10, 1951, a truce was signed at Panmunjom in July 1953, and the United States suffered 157,530 casualties, including more than 33,000 deaths from all causes and more than 23,000 combat deaths; the Vietnam War, fought against communism and North Vietnam under the belief that the fall of South Vietnam would lead other Southeast Asian nations to follow, with American troop withdrawal under Vietnamization beginning in 1969 and the last Americans leaving in April 1975; the Persian Gulf War, in which Iraqi forces invaded Kuwait in August 1990, the United Nations authorized force on Nov. 29, 1990, coalition attacks began on Jan. 17, 1991, the ground offensive opened on Feb. 23, and the war ended 100 hours later with the withdrawal of Iraqi troops and the re-raising of the Emirates flag in Kuwait City on Feb. 27; and the War on Terror, renewed after Sept. 11, 2001, when attacks on the World Trade Center and the Pentagon killed more than 3,000 people on U.S. soil, followed by U.S. action against the Taliban in Afghanistan and later the overthrow of the Iraqi government.