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The USA in WW II. Pr i or to the American invovlment. American isolitionism and non-interventionism Lend-Lease Act (1941) A total of $50.1bln (equivalent to $759 bln at 2008 prices) worth of supplies shipped to the UK, Soviet Union, France and China. Roots of the Pacific Theater conflict.
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Prior to the American invovlment • American isolitionism and non-interventionism • Lend-Lease Act (1941) • A total of $50.1bln (equivalent to $759 bln at 2008 prices) worth of supplies shipped to the UK, Soviet Union, France and China
Roots of the Pacific Theater conflict • Japan • modernisation / westernisation of Japan • Japanese expansionism • imperial policy • militarism • Invasion of Manchuria (1931) • Second Sino-Japanese War(1937) • Invasion of French Indochina (1940) • USA • American expansionism? • racial background: • Chincese Exclusion Act of 1882 • Gentlemen's Agreement of 1907 • Immigration Act of 1917 (the Asiatic Barred Zone Act) • Immigration Act of 1924 • Japanese natural resources crisis • oil resources – none • Japan relies on importation of oil from the USA • USA put enforces embargo on exportation of oil to Japan • Japanese navy faces dramatic shrtage of oil (6 months wotrh supplies – hance Japan faces being defenceless) • Japanese dillemma: negotiate or execute a preventive attack
Pearl Harbor (December 7, 1941) • four battleships sunk, four more damaged • 7 other ships sunk or destroyed • 188 aircraft destroyed • 2400 American lives lost • isolitionism ends • after Pearl Harbor the Japanese march through Southeast Asia and Cetnral Pacific:Thailand, Malaysia, Burma Singapore, the Philippines, Rabaul (Papua New Guinea) Dutch East India (Indonesia)
Japanese American Internment • approx. 120.000 Japanese Americans placed in "War Relocation Camps" • exclusion from the military • yet: approx. 20.000 Japanese Maricans served in the Army, many having signed loyalty oaths • 442nd Regimental Combat Team – most decorated unit of its size during the European campaign
Midway • between 4 and 7 June 1942 • largest use of aircraft carriers to date • a decisive battle of the Pacific Theater • momentum changes – the Japanese forces stopped • Island hopping follows
Island hopping • Guadalcanal • Iwo Jima • Okinawa
Kamikaze attacks • approx. 3800 kamikaze pilots killed • sank between 34 – 57 ships, including 3 escort carriers and 14 destroyers • damaged around 400 other ships • killed nearly 5.000 sailors, wounded another 5.000
Bobming of Tokyo and raids on other home islands cities • General Curtis LeMay • Robert McNamara • series of "night fire-raids" • most deadly: 9–10 March 1945 (25% of the city destroyed, approx. 100.000 perished in the resulting fires) • over 50% of Tokyo destroyed by the end of the war • between 220.000 – 500.000 killed in result of strategic bombings
Hiroshima and Nagasaki • Manhattan Project • Potsdam ultimatum • bombing of Hiroshima (August 6, 1945) • "Litle Boy" kills approx. 140.000, mostly civilians • bombing of Nagasaki (August 9, 1945) • "Fat Man" kills approx. 80.000, mostly civilians • August 15, 1945 – Japan announces surrender (V-J Day) • September 2, 1945 – Surrender signed
A-Bomb controversies • Did the bombings help end the war sooner? • prevent invasion of Japan? • massive losses anticipated • save lives? • 100.000 POWs, Japanese civilians, American soldiers • yet: were they war-crimes? • were they militarily unnecessary? • were they acts of state-terror? • atomic logic – new strategic questions • why was terror chosen over intimidation? • why was Nagasaki attacked? • waht would happen should American intelligence concerning the Japanese nuclear program fail? • started a nuclear era • intimidated the Soviets • secured the position of the USA as the superpower • worst American publicity move to date
Battle of the Atlantic • Lend-lease program • Convoys • Submarine warfare • U-boots • wolf-pack tactics • Surface battleship / raiders battle • sinking of Bismarck • How was the Battle of the Atlantic won? • closing of the mid-Atlantic gap" • new escorts tactics – new classes of ships – destroyer escorts, etc. • new technologies: sonar, radar • breaking of the Enigma
Enigma • German cryptographic machine used for secret military communications – deciphering of Enigma communications most crucial for the Battle of the Atlantic • first deciphered by the Polish Biuro Szyfrów (Marian Rejewski) • the Poles decide to disclose details of their work to Allies mid 1939 • Allied effort at breaking of the Enigma centered in Bletchley Park • Alan Turing • WW II cryptographic breakthroughs lead to the construction of automated logical machines and to building first computers
Enigma – construction and operation • keyboard • plugboard • entry wheel • rotors • rotor – rings - indicators • reflector • PRINCIPLE: • each time a key is pressed- electric current goes from the key, through the plug board, through the rotors, is reflected, goes back through the rotors (through a different path!), through the plug board, and to the light board) • each time a key is pressed – rotor advances one position • after the right rotore advances 26 positions the next one advances one position • a symbol is never encrypted as itself • number of possible configurations: approx. 10114 that is:
Enigma - security • 10114 = 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 of possible configurations
Enigma – operation TO ENCRYPT A MESSAGE • place rotors in the order described in the codebook and using the ring settings required by the codebook (different for ever day of year, the same for all units in a given force) • connect the ports in the plug board in the order described in the codebook • follow the "indicator procedure" • set the rotors to the initial positions required by the codebook (e.g. A R G) • type in your own setting sequence twice ( e.g. E I N ) • set the rotors to YOUR settings • type in plain text – cipher text will show on the light board TO DECRYPT THE MESSAGE • place rotors in the order described in the codebook and using the ring settings required by the codebook • connect the ports in the plug board in the order described in the codebook • set the rotors to the initial positions required by the codebook (A R G) • type in 6 first symbols of the cipher text – you know have the settings for the rotors chosen by the cipher text Enigma operator • set the rotors to the positions (E I N) deciphered from the cipher text • type in the cipher text – plaintext will show on the light board
Breaking of the Enigma • wiring of the rotors • initial settings • "cillies" • cribs • "gardening" • bombes • by 1945 Allies could read all German Enigma communications withind a day or two • Breaking of Lorenz (Fish) • Collossus • Breaking of PURPLE (Magic) – American effort to read Japanese diplomatic codes
European Theater 1942 - 1944 • Europe First • Stalin presses for the second European front – Churchill convinces Roosevelt Africa is the gate to Southern Europe • Operation Torch and North Africa Campaign • Invasion of Sicily • Gen. George Patton • Invasion of Italy • Strategic bombing of Germany SS Robert Rowan explodes hit by a German bomber
Operation Overlord - D-Day (June 6, 1944 – Invasion of Normandy) • Second front in Europe • "Europe first" • D-Day • 5000 ships involved • over 175.000 troops landing – amphibian and airborne • 2500 American lives lost • Omaha beach
European Theater 1944-1945 • Operation Cobra – from Normandy across France • liberation of Paris, August 25, 1944 • Operation Market Garden • Battle of the Bulge • Race to Berlin • May 2, 1945 – Germans surrender Belin to the Soviets • May 8, 1945 – V-E Day – German surrender signed
The Holocaust • more than a third of the Jewish global population perished – estimated nearly 6.000.000 people
Aftermath of the W II • 50.000.000 – 70.000.000 people dead • Europe in ruins • Garmany occupied and later divided • Japan humiliated and occupied • revisions of borders • population relocations – repatriations and expulsions • decolonisation • emergence of the UN • emergence of two superpowers – a bipolar world • Soviet Bloc • technological advancements
Aftermath of the W II – American Perspective • 420.000 deaths (out of 11.260.000 military personnel) • nuclear superpower • Marshall plan • period of wealth and economic stability followed • role of women • G. I. Bill (Servicemen's Readjustment Act )