WWII

World War Two in the Pacific

Greater East Asia Co-Prosperity Sphere (1942)

  • Concept Established: This ideological campaign sought to justify Japanese expansion in Asia.

Early Naval Agreements

  • Washington Naval Conference (1921-1922):

    • Established a ten-year arms limitation agreement.

    • Ratio of battleships fixed at:

    • USA: 5

    • Britain: 5

    • Japan: 3

    • Smaller limits for France and Italy set at a ratio of 1.7.

  • London Naval Treaty (April 1930):

    • Participating nations included Britain, Japan, France, Italy, and the USA.

    • Regulated submarine warfare and limited naval shipbuilding.

Japan's Departure from Naval Limitations

  • Year 1934: Japan left the London and Washington arms limitation agreements.

    • Hamaguchi Incident: Prime Minister Hamaguchi shot for agreement to naval arms limitations.

    • Following this, Japan accelerated military spending and began constructing the largest battleships.

Invasion of China

  • 1937: Japan invaded China following the Marco Polo Bridge incident, a firefight between Japanese and Chinese soldiers.

    • Hirohito did not object to expansionism due to advice from military chiefs and Prime Minister Fumimaro Konoe.

    • Hirohito expressed concern about a potential Soviet attack from the north.

    • Military Factions in Japan:

    • Kodoha faction of the Army: Led by War Minister Sadao Araki, favored a strategy called Strike North (Hokushin-ron).

    • Toseiha faction of the Navy: Supported a different approach known as Strike South (Nanshin-ron).

Shift of Military Power

  • Historical Context: The Army had significant influence in early 20th century Japan due to successes in Korea and China.

  • Events of 1936: Resignation of Araki; subsequent purge of the Kodoha faction after a failed coup led to naval dominance.

  • Soviet-Japanese Battle of Khalkin Gol (April – September 1939): After a defeat here, Japan's focus shifted to the Pacific and the Nanshin-ron strategy.

  • Neutrality Pact (April 1941): Signed between Japan and the Soviet Union.

Precipitating War with the United States

  • Initial Opposition to Axis Alliance: Hirohito was initially against a coalition with Nazi Germany and Italy.

  • Tripartite Pact: Formed on September 27, 1940, aligning Japan with Germany and Italy as Axis Powers.

  • Japanese Military Actions (July 1941): Troops sent to southern Indochina, threatening British and Dutch interests.

  • Western Response: The US, UK, and other Western governments froze Japanese assets and imposed a total oil embargo.

Ultimatum and Pearl Harbor Attack

  • November 20, 1941: Japan called for an end to American aid to China, seeking to restore oil and resource supplies.

  • American Counter-Proposal (November 26, 1941): Required evacuation of all Japanese forces from China and non-aggression pacts with Pacific powers; deemed unacceptable by Japan.

  • Pearl Harbor Attack (December 7, 1941): Aimed to prevent American intervention in the Pacific; invasion of Malaya commenced simultaneously.

Progress of the War

  • Pacific War Duration: Generally recognized as spanning from 1937 to 1942, marking Japan's rapid territorial gains.

Countries and Territories Involved

  • **Japan's Expansions: **

    • China (invaded December 1941)

    • French Indochina (July 1940, under Japanese control)

    • Thailand (became a Japanese ally in December 1941)

    • Philippines, British Malaya, and Pacific Islands under Japanese occupation by early 1942.

  • Allied Nations:

    • The United States, Britain, China, Australia, and several others formally declared war on Japan,

    • Notably, the USSR maintained neutrality due to conflict with Germany.

  • Japanese Military Victories: Successfully conquered Burma, Malaya, the Dutch East Indies, Singapore, and the Philippines by May 1942.

    • Notable Defeat: Japan only faced defeat at Changsha, China, in January 1942.

Maps and Territorial Expansion

  • Japanese Empire Map (1939 - 1942): Indicates territories acquired by Japan by 1942, showing significant extensions into the Pacific, China, and Indochina.

Key Battles and Turning Points

  • Midway Atoll (June 1942): The Americans broke Japanese naval codes; significant American victory shifted the war's tide.

  • Guadalcanal (Early 1943): Marked another major defeat for Japan.

Late War Developments

  • December 1944 Events::

    • Japanese forces in China and Indochina were linked.

    • American forces advanced against Mariana and Palau Islands, leading to decisive victory at the Battle of the Philippine Sea in June, resulting in the resignation of Prime Minister Hideki Tojo.

Key Battles in Late 1944 and 1945

  • Battle of Leyte Gulf (October 1944): Largest naval battle in the Pacific War; Japanese Navy lost 26 warships.

  • Consequences of Philippine Loss: Japan was isolated from its occupied territories and resources, particularly oil.

  • Final Stages: American capture of Iwo Jima (March 1945) and Okinawa (June 1945).

  • Destruction of Japanese Cities: American air force targeted major urban areas and submarine blockade affected supply lines.

Conclusion of the War

  • Estimated Casualties from Potential Invasion: High estimation of casualties if there were a direct invasion of Japan by American forces.

  • Hiroshima and Nagasaki: Japan ignored the terms set forth in the Potsdam Declaration.

    • Atomic bombs were dropped on:

    • August 6: Hiroshima (90,000 to 160,000 deaths).

    • August 9: Nagasaki (40,000 to 80,000 deaths).

Japanese Surrender

  • Soviet Union's Role: On August 5, 1945, the USSR abrogated the neutrality pact.

  • Manchurian Strategic Offensive Operation (August 9 - September 2): Involved 1.5 million Soviet troops attacking multiple strategic points in Manchuria.

  • Japanese Surrender Date: August 15, 1945; official surrender signed on the USS Missouri on September 2, 1945.