https://historyandwar.org/2021/12/05/pacific-war-2-attack-on-pearl-harbor/ https://historyandwar.org/2022/12/07/why-did-japan-attack-pearl-harbor/ While this was understood only by a few people, by 1941. Japan and the United States had been on a collision course for a whole decade. Slide towards the conflict started arguably in 1902., with the signing of the Anglo-Japanese alliance between the Great Britain and Japan. But that the two countries were on a collision course only became clear in 1931., when Japan conquered Manchuria. In 1937., Japan also invaded northern China, and two years later its attention turned southwards with the conquest of island of Hainan. After it, Japan turned its attention onto Malaya, Phillipines and the Dutch East Indies. United States, by contrast, were supporting the Japan-hostile government of Chang Kai Shek, and also European colonial efforts in Asia. This was happening right at the time when Japan was repeating the parole of “Asia to Asians”. Japanese kept talking about the great eastern sphere of common progress, while they were in fact searching for the natural resources their islands did not have. Fall of France in June 1940. gave Japan a good excuse to send troops to French Indochina, and on 27th September it signed a Tripartite Pact with the Axis powers. As US sympathies were clearly with the Allies, President Roosevelt introduced an embargo on all key materials except for oil. Japanese called this confrontation of two powers Taihei-yono-go: “Cancer of the Pacific”. Attempting to find a diplomatic solution, Japanese government recalled a retired admiral Kichisaburo Nomura, assigning him as a Japanese ambassador to United States in January 1941. But plans were already being made for war, and the US sanctions only increased Japanese determination to fight. US ambassador to Japan, Joseph Grew, correctly predicted that Japan will “rather carry out a national harakiri than bow under foreign pressure”. While United States government wanted to avoid war so as to have free hands to help Allies in Europe, it was clear the war was unavoidable due to actions of both sides. And Japan was heading for war. Thus, US government decided to adopt “wait-and-see” approach, avoiding any kind of preemtive strike so as to reveal the Japan as true aggressor.

1. Why Did Japan Attack the Pearl Harbor
Preliminary Moves and Attack on the Pearl Harbor

2. Introduction
●
Japan attacked Pearl Harbor on 7th
December 1941
● Basic reason was the diplomatic conflict between
United States and Japan over the Japanese colonial
expansion, especially in China where US supported
the nationalist government of Chang Kai Shek
● Japan was humiliated by Perry's visit in 1853., and
Shogunate had to agree to a series of unequal
treaties
● Shogunate collapsed in 1868., and Japan began
modernization under the Meiji leaders

3. Situation in Japan
● Modernization efforts however were hampered by
the lack of natural resources
● Iron, coal and food all had to be secured abroad, and
so Japan looked to acquire colonies
● First steps were conquest of Korea and Manchuria in
the Sino-Japanese War of 1894-5 and Russo-
Japanese War of 1904-5
● 1920s were time of peaceful relations and free trade,
but the economic crisis after 1929 forced Japan to
reassess its position

4. Situation in Japan
● Kanto Earthquake in 1923 led to social readjustment
● Liberalism was abandoned as its deletrious effects
on the society was recognized, but
overcompensation led to rampant militarism and
chauvinism
● Population was subjected to and brought up in an
extreme and inhumane corruption of the traditional
Japanese bushido code
● Real power was in the hands of industrial and
financial magnates, and they wanted new trade areas

5. Colonial Ambitions
● In 1929. - 1931., Japan reassessed its situation
● Scarcity of resources, growing population and an
economic crisis convinced Japan that solution was
to be found in colonial expansion
● Already by 1927.-1928. Japan was experiencing
depression and high unemployment
● In 1929., the Great Depression made things even
more difficult

6. War in China
● But USSR and China were rearming and threatened
Japanese economic position in Manchuria
● In 1931. Japan overran Manchuria and formed a
puppet state of Manchukuo
● Attack on China began in 1937.; neither European
powers nor the United States reacted
● By 1938., Japan had conquered almost entirety of
coastal China, all the way to the French Indochina
● These conquests were formally recognized by the
western powers

7. Road to War
● Tensions grew with fall of France in 1940., as Japan
sent troops to occupy the French Indochina
● United States banned export of iron ore, scrap iron
and steel to Japan
● Japan acquired from France large areas of Laos and
Cambodia, thus approaching Malaysia and
concerning the Allies

8. Road to War
● In 1941., Japan signed a Tripartite Pact with
Germany and Italy
● This caused United States, Great Britain,
Netherlands and China to establish oil embargo
against Japan
● In a single stroke, Japan had lost 94% of its oil
● Looking at potential options, Japan decided to go to
war

9. War Plans
● Original plans called just for the conquest of Dutch
Indonesia
● Admirals believed this acquisition could be made
quickly and with little risk
● Indonesian resources could solve Japan's resource
crisis
● Potentially, French colonies may also be conquered
with no threat of reprisal
● War against Britain and United States was to be
avoided

10. War Plans
● Army wanted an all-out war
● More importantly, Army generals wanted to win
their internal war against the Navy
● Generals wanted to conquer China and then turn
against the Soviet Union
● This led to Japan signing the Tripartite Pact in 1941
● Generals began planning campaigns with no input
by the Navy and also expanded the scope

11. Japan Goes to War
● Plan now called for conquest of Malaya, Burma,
Siam, Indonesia and the Phillipines
● Navy was not happy
● Opponent was too powerful, distances made
logistics and operational coordination difficult, and
it was the navy that will carry the weight of the war.
● But the Army won out, and campaign was given a
go-ahead

12. Japan Goes to War
● Isoroku Yamamoto originally opposed the war
against the United States
● But in 1940. he began advocating for war against
United States and Great Britain
● War would begin with a surprise attack, much as
Japan did against Russian Empire in 1904
● Plan included multiple concurrent attacks, but the
primary attack was aimed against the Pearl Harbor