The USA in WW II

Prior to the American invovlmentAmerican isolitionism and non-interventionismLend-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 conflictJapanmodernisation / westernisation of JapanJapanese expansionismimperial policymilitarismInvasion of Manchuria (1931)Second Sino-Japanese War(1937)Invasion of French Indochina (1940)USAAmerican expansionism?racial background:Chincese Exclusion Act of 1882Gentlemen's Agreement of 1907Immigration Act of 1917 (the Asiatic Barred Zone Act) Immigration Act of 1924Japanese natural resources crisisoil resources noneJapan relies on importation of oil from the USAUSA put enforces embargo on exportation of oil to JapanJapanese 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 damaged7 other ships sunk or destroyed188 aircraft destroyed2400 American lives lostisolitionism 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)

USS West Virgninia burns

USS Arizona explodes

Japanese American Internmentapprox. 120.000 Japanese Americans placed in "War Relocation Camps"exclusion from the militaryyet: approx. 20.000 Japanese Maricans served in the Army, many having signed loyalty oaths442nd Regimental Combat Team most decorated unit of its size during the European campaign

Midwaybetween 4 and 7 June 1942largest use of aircraft carriers to datea decisive battle of the Pacific Theatermomentum changes the Japanese forces stoppedIsland hopping follows

Island hoppingGuadalcanalIwo JimaOkinawa

Kamikaze attacksapprox. 3800 kamikaze pilots killedsank between 34 57 ships, including 3 escort carriers and 14 destroyersdamaged around 400 other shipskilled nearly 5.000 sailors, wounded another 5.000

Bobming of Tokyo and raids on other home islands citiesGeneral Curtis LeMayRobert McNamaraseries of "night fire-raids"most deadly: 910 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 warbetween 220.000 500.000 killed in result of strategic bombings

Hiroshima and NagasakiManhattan ProjectPotsdam ultimatumbombing of Hiroshima (August 6, 1945)"Litle Boy" kills approx. 140.000, mostly civiliansbombing of Nagasaki (August 9, 1945)"Fat Man" kills approx. 80.000, mostly civiliansAugust 15, 1945 Japan announces surrender (V-J Day)September 2, 1945 Surrender signed

A-Bomb controversiesDid the bombings help end the war sooner?prevent invasion of Japan?massive losses anticipatedsave lives?100.000 POWs, Japanese civilians, American soldiersyet: were they war-crimes?were they militarily unnecessary?were they acts of state-terror?atomic logic new strategic questionswhy was terror chosen over intimidation?why was Nagasaki attacked?waht would happen should American intelligence concerning the Japanese nuclear program fail?

started a nuclear eraintimidated the Sovietssecured the position of the USA as the superpowerworst American publicity move to date

Battle of the AtlanticLend-lease programConvoysSubmarine warfareU-bootswolf-pack tacticsSurface battleship / raiders battlesinking of BismarckHow 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, radarbreaking of the Enigma

EnigmaGerman cryptographic machine used for secret military communications deciphering of Enigma communications most crucial for the Battle of the Atlanticfirst deciphered by the Polish Biuro Szyfrw (Marian Rejewski)the Poles decide to disclose details of their work to Allies mid 1939Allied effort at breaking of the Enigma centered in Bletchley ParkAlan TuringWW II cryptographic breakthroughs lead to the construction of automated logical machines and to building first computers

Enigma construction and operationkeyboardplugboardentry wheelrotorsrotor rings - indicatorsreflectorPRINCIPLE: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 positionafter the right rotore advances 26 positions the next one advances one positiona symbol is never encrypted as itselfnumber of possible configurations: approx. 10114 that is:

Enigma - security10114 = 10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 of possible configurations

Enigma operationTO ENCRYPT A MESSAGEplace 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 codebookfollow 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 settingstype in plain text cipher text will show on the light board

TO DECRYPT THE MESSAGEplace rotors in the order described in the codebook and using the ring settings required by the codebookconnect the ports in the plug board in the order described in the codebookset 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 operatorset the rotors to the positions (E I N) deciphered from the cipher texttype in the cipher text plaintext will show on the light board

Breaking of the Enigmawiring of the rotorsinitial settings"cillies"cribs"gardening"bombesby 1945 Allies could read all German Enigma communications withind a day or twoBreaking of Lorenz (Fish)CollossusBreaking of PURPLE (Magic) American effort to read Japanese diplomatic codes

European Theater 1942 - 1944 Europe FirstStalin presses for the second European front Churchill convinces Roosevelt Africa is the gate to Southern EuropeOperation Torch and North Africa CampaignInvasion of SicilyGen. George PattonInvasion of ItalyStrategic bombing of GermanySS 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-Day5000 ships involvedover 175.000 troops landing amphibian and airborne2500 American lives lostOmaha beach

European Theater 1944-1945Operation Cobra from Normandy across Franceliberation of Paris, August 25, 1944Operation Market GardenBattle of the BulgeRace to BerlinMay 2, 1945 Germans surrender Belin to the SovietsMay 8, 1945 V-E Day German surrender signed

Tehran, Yalta, Potsdam Conferences

Aftermath of the W II

The Holocaustmore than a third of the Jewish global population perished estimated nearly 6.000.000 people

Aftermath of the W II50.000.000 70.000.000 people deadEurope in ruinsGarmany occupied and later dividedJapan humiliated and occupiedrevisions of borderspopulation relocations repatriations and expulsionsdecolonisationemergence of the UNemergence of two superpowers a bipolar worldSoviet Bloctechnological advancements

Aftermath of the W II American Perspective420.000 deaths (out of 11.260.000 military personnel)nuclear superpowerMarshall planperiod of wealth and economic stability followedrole of womenG. I. Bill (Servicemen's Readjustment Act )