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Course: US history > Unit 7
Lesson 5: World War II- Beginning of World War II
- 1940 - Axis gains momentum in World War II
- 1941 Axis momentum accelerates in WW2
- Pearl Harbor
- FDR and World War II
- Japanese internment
- American women and World War II
- 1942 Tide turning in World War II in Europe
- World War II in the Pacific in 1942
- 1943 Axis losing in Europe
- American progress in the Pacific in 1944
- 1944 - Allies advance further in Europe
- 1945 - End of World War II
- The Manhattan Project and the atomic bomb
- The United Nations
- The Second World War
- Shaping American national identity from 1890 to 1945
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Pearl Harbor
December 7, 1941 was a "date which will live in infamy," according to Franklin Delano Roosevelt. The surprise attack on Pearl Harbor by the Japanese led the United States to enter World War II.
Overview
- On the morning of December 7, 1941, Japan attacked the US naval base at Pearl Harbor, Hawaii.
- The surprise attack by some 350 Japanese aircraft sunk or badly damaged eighteen US naval vessels, including eight battleships, destroyed or damaged 300 US aircraft, and killed 2,403 men.
- Across the nation, Americans were stunned, shocked, and angered. The attack turned US public opinion in favor of entering the Second World War. The United States declared war on Japan on December 8, 1941.
- Japan’s allies, Germany and Italy, declared war on the United States on December 11. The United States responded in kind, and therefore entered World War II.
The Pearl Harbor attack
The Japanese surprise attack on Pearl Harbor began just before 8 a.m. local time Sunday morning, December 7, 1941. For over an hour, in two waves, some 350 Japanese aircraft—having taken off from six aircraft carriers 230 miles north of Oahu—attacked the naval base. Japanese forces wreaked havoc on US naval vessels and on US aircraft on the island’s airfield.
The American people were shocked, bewildered, surprised, and angered by the attack. On December 8, President Roosevelt addressed a joint session of Congress in the Capitol, his words broadcast on radio to the nation: “Yesterday, December 7, 1941—a date which will live in infamy—the United States of America was suddenly and deliberately attacked by naval and air forces of the Empire of Japan.”
In his address, Roosevelt asked Congress to declare war against Japan, which it did that day. Three days later, Japan’s allies Germany and Italy declared war on the United States, and Congress reciprocated the same day. All previous domestic opposition to US entry into the war ceased. The United States was now immersed in a war it would conduct simultaneously in Europe and the Pacific.
Motive for the attack
The Japanese government decided to attack Pearl Harbor after the United States cut off US oil exports to Japan in the summer of 1941. Japan relied on the United States for eighty percent of its oil, and without US oil supplies its navy would be unable to function. In attacking Pearl Harbor the Japanese hoped to cripple or destroy the US Pacific fleet so that the Japanese navy would have free reign in the Pacific.
Japan was also motivated strategically by ideas of creating an Asian co-prosperity sphere—“Asia for Asians”—in which Japan would take over the Asian colonial holdings of Europe and the United States. With the British, French, and Dutch caught up in the war in Europe, the Japanese believed the European powers would be unable to defend their Asian colonial holdings. Indeed, in the eight hours following the Pearl Harbor attack, Japan also attacked British-held Singapore, Hong Kong, and Malaya, and the US territorial possessions of the Philippines, Guam, and Wake Island.
Forewarnings about the attack
The United States was caught unprepared for the attack on Pearl Harbor, but things might have turned out differently were it not for some bad luck. The United States had broken the Japanese diplomatic code in project “Magic,” and General George Marshall, having been handed a decoded Japanese message on the very day of the attack, had sent word to the US base at Pearl Harbor prior to the assault to “be on the alert.” Atmospheric conditions delayed transmission of Marshall’s message, and it did not arrive until after the attack.
Moreover, the United States had known that a Japanese attack was imminent somewhere in the Pacific, but US military and government personnel had thought the Philippines or some other area of the South Pacific closer to Japan was the likely target. Pearl Harbor was 3,500 miles from Japan and had seemed to the US government and military an unlikely target.
After Pearl Harbor, the United States rapidly mobilized for World War II.
What do you think?
What motives did Japan have in attacking the US naval base at Pearl Harbor?
What was the American response to the Japanese attack?
Do you think the United States would have entered World War II if the Japanese had not bombed Pearl Harbor? Why or why not?
Want to join the conversation?
Was the U.S powerful back then and did Japan know.(16 votes)
Japan was fully aware of America's power. Until American Commodore Matthew C. Perry arrived on Japan's shore in 1853, Japan had been a mostly closed country for the previous 250 years, strictly regulating interactions and trade with foreigners. Perry demanded Japan to open to trade with the West. With the arrival of Perry, Japan realized they were behind the Western world (Europe and America), and from the start of the Meiji (Enlightenment) Era in 1868, Japan began sending people to Europe and America to learn everything they could in order to catch up with the West. Because of its very limited resources, Japan realized it needed natural resources to industrialize and compete with the West. They viewed Europe's power through their massive empires, and they emulated by invading and conquering other Asian countries. The oil embargo placed on Japan by the US threatened Japan's expansion plan for its empire, so while they made diplomatic efforts to get the embargo lifted (on terms to still be allowed to take over desired territories), they prepared for war.(40 votes)
does this quote, "a day that will live in infamy", still has meaning to this day? or is it true to this day?(8 votes)
From the author:I think so! The United States still marks December 7th every year as the anniversary of Pearl Harbor.(21 votes)
Why did japan not think about how powerful the US and not think about the cons(11 votes)- Japan new how powerful America was and that is why they wanted to destroy them and gain control over the Pacific.(3 votes)
I have read many other articles on WWII, and some of them have suggested that the US wanted to fight. The US Secretary of war, Henry L. Stimson of the US wrote in his diary, “The question was how we should maneuver them [Japan] into firing the first shot without allowing too much danger to ourselves.” After the Bombing of Pearl Harbor, Stimson affirmed, “my first feeling was of relief… that a crisis had come in a way which would unite all our people.”
If the US cryptographers had broken the code of Japan (which they had) and had sent a telegram to Pearl Harbor, why was that telegram not sent as urgent. How could the attack have been a "shock" to America? Why did the US want japan to fight against us?(8 votes)
From my understanding, it was a shock because many Americans didn't fully realize that 1)Japan was a serious threat and 2)the fact that America could be attacked, especially since they technically were not involved in the conflict. As to why some people wanted to fight, they saw the rising threat of fascism and wanted to counter it to protect the US. The reason the US didn't join the war until it was attacked was that people still remembered the atrocities from WWI and didn't want to sacrifice more American lives to protect other countries. After Pearl Harbor, they had a real reason to defend themselves.(10 votes)
If Japan had so little resources how did they have the money to be having war with all these countries? wouldn't you have better things to do? where did they get all the resources to build all their aircraft, guns and warships?(7 votes)
Japan tried to capture resources from other nations they invaded. At the beginnig of the war, this strategy was working ,because Japan occupied nearby countries, but as the U.S recaptured this countries, Japan started to fall apart, because in a war such as world war 2 resources such as oil are desperately needed to keep communication lines and to maintain wartime production. hope i have helped =)(10 votes)
- In reality, Japan attacked the U.S naval base due to oil embargo. Actually, the U.S cut off its exportation of oil which caused Japanese machines to cease to function. Having been encountered a surprising attack, the U.S could not wait to fight back, even the opposing groups of war in the U.S. I do not think the U.S could have entered the WW2 if it had not been attacked by imperial Japan. We can consider two possible hidden reasons. Firstly, there was tension in America, and some anti-war groups did not want the U.S to intervene in war. Secondly, the U.S had merely recovered from the Great Depression, and it had duties to revive its economy.(4 votes)
The Japanese had a reason to bomb Pearl Harbor because of the US oil embargo but why do they have to do that? I still can't understand it and there is no way to stop this bombing. The oil embargo is kinda like an act of war. Why though?(1 vote)
Because of the oil embargo, the Japanese knew the US would militarily oppose Japan's planned expansion in the Pacific. So the Japanese decided to strike first and try to catch the Americans sleeping.(7 votes)
- Was Midway a U.S controlled Island.(1 vote)
Midway was claimed by the United States on August 28, 1867 long before the attack on Pearl Harbor.
It is actually part of the Hawaiian archipelago, but is the only island that is not part of the STATE of Hawaii. If observes Samoa Time which is one hour behind Hawaii time.(5 votes)
how would we know if the Japanese were about to attack(3 votes)
Back then, we had radar that was decent. But, the radar operators demeaned the incoming Japanese ships as blips or errors in the system.
Currently, we have satellites, ships, submarines, planes, and more checking the world over for attacks of any kind. It is state-of-the-art equipment and multiple people and machines are monitoring it everywhere. An attack as large scale as Pearl Harbor on America is almost impossible nowadays.(2 votes)
did japan have to make a big plan to attack pearl harbor(1 vote)
Yes. In fact, the Japanese had a specific group, part of the Navy, called the Kamikaze. The Kamikazee crashed their own aircraft into opposing naval targets to destroy them. Also, Japan took over many areas in the Pacific which of course requires big plans. So yes, they made a big plan.(5 votes)
