<P> The origins of the United States military can be traced to the Americans' fight for independence from their former colonial power, Great Britain, in the War for independence (1775--83). The three bloodiest conflicts have been American Civil War (1861--65), World War I (1917--1918) and World War II (1941--45). Since 1945 the United States has been almost constantly at war, notably in the Korean War (1950--1953), Vietnam War (1955--1975), the War in Afghanistan (2001--present) and various conflicts in the Middle East . For most of its existence, America has been involved in one or another military conflict . </P> <P> The term Casualty in warfare can often be confusing . It often does not refer to those that are killed on the battlefield; rather, it refers to those who can no longer fight . This can include disabled by injuries, disabled by psychological trauma, captured, deserted, or missing . A casualty is just a soldier who is no longer available for the immediate battle or campaign, the major consideration in combat; the number of casualties is simply the number of members of a unit who are not available for duty . For example during the Seven Days Battles in the American Civil War (June 25 to July 1, 1862) there were 5,228 killed, 23,824 wounded and 7,007 missing or taken prisoner for a total of 36,059 casualties . The word casualty has been used in a military context since at least 1513 . In this article the numbers killed refer to those killed in action, killed by disease or someone who died from their wounds . </P> <Table> <Tr> <Th> Battle, siege, or offensive </Th> <Th> Conflict </Th> <Th> Date </Th> <Th> Estimated number killed </Th> <Th> Opposing force </Th> <Th> References </Th> </Tr> <Tr> <Td> Battle of Normandy / Northern France </Td> <Td> World War II </Td> <Td> 1944--06 - 06! June 6 to September 14, 1944 </Td> <Td> 34,137 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Meuse - Argonne Offensive </Td> <Td> World War I </Td> <Td> 1918--09 - 26! September 26 to November 11, 1918 </Td> <Td> 26377! 26,277 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Okinawa </Td> <Td> World War II </Td> <Td> 1945--04 - 01! April 1 to June 22, 1945 </Td> <Td> 20195! 20,195 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of the Bulge </Td> <Td> World War II </Td> <Td> 1944--12 - 16! December 16, 1944, to January 25, 1945 </Td> <Td> 19276! 19,276 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Hürtgen Forest </Td> <Td> World War II </Td> <Td> 1944--09 - 19! September 19, 1944, to February 10, 1945 </Td> <Td> Over 12,000 ~ killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Luzon </Td> <Td> World War II </Td> <Td> 1945--01 - 09! January 9 to August 15, 1945 </Td> <Td> 10640! 10,640 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Côte d'Azur / Southern France </Td> <Td> World War II </Td> <Td> 1944 - 08 - 15! August 15 to September 14, 1944 </Td> <Td> 7,301 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Guadalcanal </Td> <Td> World War II </Td> <Td> 1942--08 - 07! August 7, 1942, to February 9, 1943 </Td> <Td> 7100! 7,100 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Gettysburg </Td> <Td> American Civil War </Td> <Td> 1863--07 - 06! July 1 to July 3, 1863 </Td> <Td> 7,058 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Operation Nordwind </Td> <Td> World War II </Td> <Td> 1944--12 - 31! December 31, 1944, to January 25, 1945 </Td> <Td> 7,000 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Iwo Jima </Td> <Td> World War II </Td> <Td> 1945--02 - 16! February 16 to March 26, 1945 </Td> <Td> 6,821 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Lorraine Campaign </Td> <Td> World War II </Td> <Td> 1944--09 - 01! September 1 to December 18, 1944 </Td> <Td> 6,657 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Anzio </Td> <Td> World War II </Td> <Td> 1944--01 - 22! January 22 to June 5, 1944 </Td> <Td> 5,538 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Seven Days Battles </Td> <Td> American Civil War </Td> <Td> 1862--06 - 25! June 25 to July 1, 1862 </Td> <Td> 5,228 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Pusan Perimeter </Td> <Td> Korean War </Td> <Td> 1950--08 - 04! August 4 to September 18, 1950 </Td> <Td> 4,599 killed </Td> <Td> North Korea </Td> <Td> </Td> </Tr> <Tr> <Td> Chinese Second Phase Offensive in North Korea </Td> <Td> Korean War </Td> <Td> 1950--11 - 25! November 25 to December 15, 1950 </Td> <Td> 4,538 killed </Td> <Td> China </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Spotsylvania </Td> <Td> American Civil War </Td> <Td> 1864--05 - 08! May 8 to May 21, 1864 </Td> <Td> 4,240 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Chickamauga </Td> <Td> American Civil War </Td> <Td> 1863--09 - 19! September 19 to September 20, 1863 </Td> <Td> 3,968 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of the Wilderness </Td> <Td> American Civil War </Td> <Td> 1864--05 - 05! May 5 to May 7, 1864 </Td> <Td> 3,741 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Antietam </Td> <Td> American Civil War </Td> <Td> 1862--09 - 17! September 17, 1862 </Td> <Td> 3,654 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Leyte </Td> <Td> World War II </Td> <Td> 1944--10 - 17! October 17 - December 26, 1944 </Td> <Td> 3,593 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Shiloh </Td> <Td> American Civil War </Td> <Td> 1862--04 - 06! April 6 to April 7, 1862 </Td> <Td> 3,482 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Saipan </Td> <Td> World War II </Td> <Td> 1944--06 - 15! June 15 to July 9, 1944 </Td> <Td> 3,426 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Chancellorsville </Td> <Td> American Civil War </Td> <Td> 1863--04 - 30! April 30 to May 6, 1863 </Td> <Td> 3,330 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Tet Offensive </Td> <Td> Vietnam War </Td> <Td> 1968--01 - 30! January 30 to September 23, 1968 </Td> <Td> 3,178 Killed </Td> <Td> North Vietnam </Td> <Td> </Td> </Tr> <Tr> <Td> Operation Diadem (part of Battle of Monte Cassino) </Td> <Td> World War II </Td> <Td> 1944--05 - 11! May 11--18, 1944 </Td> <Td> 3,145 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Second Battle of Bull Run </Td> <Td> American Civil War </Td> <Td> 1862--08 - 26! August 26 to August 30, 1862 </Td> <Td> 3,052 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Stones River </Td> <Td> American Civil War </Td> <Td> 1862--12 - 31! December 31, 1862 to January 2, 1863 </Td> <Td> 3,024 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Chosin Reservoir </Td> <Td> Korean War </Td> <Td> 1950--11 - 27! November 27 to December 13, 1950 </Td> <Td> 2,840 ~ killed </Td> <Td> China </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Sicily </Td> <Td> World War II </Td> <Td> 1943--07 - 09! July 9 to August 17, 1943 </Td> <Td> 2,811 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Leyte Gulf </Td> <Td> World War II </Td> <Td> 1944--10 - 23! October 23--25, 1944 </Td> <Td> 2,800 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Cold Harbor </Td> <Td> American Civil War </Td> <Td> 1864--05 - 21! May 21 to June 12, 1864 </Td> <Td> 2,632 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> D - day (first day of Operation Overlord) </Td> <Td> World War II </Td> <Td> 1944--06 - 06! June 6, 1944 </Td> <Td> 2,499 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Pearl Harbor Attack </Td> <Td> World War II </Td> <Td> 1941--12 - 07! December 7, 1941 </Td> <Td> 2,403 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Peleliu </Td> <Td> World War II </Td> <Td> 1944--09 - 15! September 15 to November 25, 1944 </Td> <Td> 2,336 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Aachen </Td> <Td> World War II </Td> <Td> 1944 - 09 - 12! September 12 to October 21, 1944 </Td> <Td> 2,000 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Ruhr Pocket </Td> <Td> World War II </Td> <Td> 1945 - 04 - 01! April 1 to April 18, 1945 </Td> <Td> 2,000 ~ killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Franklin </Td> <Td> American Civil War </Td> <Td> 1864--11 - 30! November 30, 1864 </Td> <Td> 1,939 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Second Battle of the Marne </Td> <Td> World War I </Td> <Td> 1918--07 - 15! July 15 to August 6, 1918 </Td> <Td> 1,926 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Po Valley Offensive </Td> <Td> World War II </Td> <Td> 1945 - 04 - 06! April 5 to May 8, 1945 </Td> <Td> 1,914 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Fredericksburg </Td> <Td> American Civil War </Td> <Td> 1862--12 - 11! December 11 to December 15, 1862 </Td> <Td> 1,892 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Guam </Td> <Td> World War II </Td> <Td> 1944--07 - 21! July 21 to August 10, 1944 </Td> <Td> 1,777 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Seven Pines </Td> <Td> American Civil War </Td> <Td> 1862--05 - 31! May 31 to June 1, 1862 </Td> <Td> 1,770 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Tarawa </Td> <Td> World War II </Td> <Td> 1943--11 - 20! November 20 to November 23, 1943 </Td> <Td> 1,759 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Salerno </Td> <Td> World War II </Td> <Td> 1943--09 - 03! September 3 to September 16, 1943 </Td> <Td> 1,635 ~ killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Operation Undertone </Td> <Td> World War II </Td> <Td> 1945 - 3 - 15! March 15 to March 24, 1945 </Td> <Td> 1,600 ~ killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of the Ch'ongch'on River </Td> <Td> Korean War </Td> <Td> 1950--11 - 25! November 25 to December 2, 1950 </Td> <Td> 1,489 killed </Td> <Td> China </Td> <Td> </Td> </Tr> <Tr> <Td> Task Force Faith </Td> <Td> Korean War </Td> <Td> 1950--11 - 27! November 27 to December 2, 1950 </Td> <Td> 1,450 ~ killed </Td> <Td> China </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Perryville </Td> <Td> American Civil War </Td> <Td> 1862--10 - 08! October 8, 1862 </Td> <Td> 1,422 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Chattanooga </Td> <Td> American Civil War </Td> <Td> 1863--09 - 21! September 21 to November 25, 1863 </Td> <Td> 1,114 killed </Td> <Td> Confederacy </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Belleau Wood </Td> <Td> World War I </Td> <Td> 1918--06 - 01! June 1 to June 26, 1918 </Td> <Td> 1,062 killed </Td> <Td> Germany </Td> <Td> </Td> </Tr> <Tr> <Td> Battle of Mindanao </Td> <Td> World War II </Td> <Td> 1945 - 03 - 10! March 10 to August 15, 1945 </Td> <Td> 1,041 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> <Tr> <Td> Battle for Manila (part of Battle of Luzon) </Td> <Td> World War II </Td> <Td> 1945--02 - 03! February 3 to March 3, 1945 </Td> <Td> 1,010 killed </Td> <Td> Japan </Td> <Td> </Td> </Tr> </Table> <Tr> <Th> Battle, siege, or offensive </Th> <Th> Conflict </Th> <Th> Date </Th> <Th> Estimated number killed </Th> <Th> Opposing force </Th> <Th> References </Th> </Tr>

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