Why did japan attack the US in 1941?

Answer 1

America let them to get America into war fever mode. We now know America had the Japanese codes in late 1940, and sacrificed its own people Aztec style to cook up war fever back home. It worked!

Answer 2

Main reason is that US took strong embargo on export to Japan. This was a trigger.

US had already know Japan would to take part in the WW2 in 1941 (WW2 was from 1939).
And as other said, Japan made a declaration of war. But Washington D.C never told the fact to Hawaii.
America needed any "reason" or "excuse" to take part in the war. Because there was huge protest against war domestically at that time.
The code which Japan was using is PURPLE. And the US broke and knew it.
"It was broken by a team from the US Army Signals Intelligence Service, then directed by William Friedman. The team was led by Frank Rowlett."

http://en.wikipedia.org/wiki/PURPLE

"The decrypted PURPLE traffic, and Japanese messages generally, was the subject of acrimonious hearings in Congress post-WW-II in connection with an attempt to decide who, if anyone, had allowed the disaster at Pearl Harbor to happen and who therefore should be blamed. It was during those hearings that the Japanese learned, for the first time, that the PURPLE cypher machine had indeed been broken."

And this would be your help as well.
“Churchill and Roosevelt knew about Pearl Harbor in advance”
http://www.winstonchurchill.org/i4a/pages/index.cfm?pageid=951

Answer 3

The United States stop trading with Japan because of it's brutal tactics in China and Korea. Which put a big dent in Japan's oil imports.

Japan though the attack was going to be far more crippiling to the US Navy and underestimated the American fighting spirit and the attack backfired big time. Japan expected the US to cave in and lift the embargos instead the US declared war.

Answer 4

Japan attacked Pearl Harbor because the U.S. enacted an embargo on all oil supplies to Japan. The reason for the embargo was because Japan had invaded China. The U.S. embargo cut-off 90% of Japans resources, prohibiting exports of steel, scrap iron and fuel.

Another reason was when Japan went ahead to invade the remainder of Indochina, including Burma, America would surely take action.

The place the Japanese considered to be their most prized invasion possession was the Dutch East Indies (oil). Many historians believe that without a reliable source of oil Japan would have been crushed under the United States Embargo.

The Japanese drastically miscalculated America's resolve once an attack on Pearl Harbor had occurred.

Fortunately for America it's aircraft carriers were not at Pearl Harbor on December 7th.; they were out at sea. This vital portion of the American fleet was spared destruction and enabled America to stagger to it's feet and retaliate. The fleet oil tank farm at Pearl Harbor was also spared, later providing a much needed supply of bunker fuel.

George E. Elliott Jr., whose unheeded warning about approaching aircraft as seen on his radar screen just after 7 a.m., due North, 137 miles out at sea, was brushed aside by his superiors as a formation of B17 Flying Fortresses from California were due to land in Hawaii "soon." Elliott and another private, Joseph L. Lockard, were on duty at Kakuku Point on the Northern tip of the island of Oahu. The men continued to observe the radar blip until 7:45 a.m. when the equipment was shut down because it was felt there had been a malfunction. 10 minutes later the Japanese aircraft began the attack on Pearl Harbor. WW ll was declared the following day by President Roosevelt against Japan.

George E. Elliott passed away December 20, 2003 at Port Charlotte, Florida from a stroke. He was 85.

Answer 5

The U. S. was their only competition in the Pacific.

Where the Japanese failed is that they didn't follow up Pearl Harbor with more strikes. They should have sent every available ship to Hawaii to mop up the survivors, then established a base in Hawaii from which to strike the West Coast.

If you're going to go to war...you might as well go all the way.

Answer 6

They were afraid that the US may enter the war, and decided that their best bet to win was to cripple the US military before the US did so.

They did not expect the response of the steelworkers in Pittsburgh, and the shipbuilders the world over, as the biggest naval group in history was rebuilt in six months to full strength.

Answer 7

They were told that the US was involved in the attack on 9/11

Answer 8

Oil was the reason. Japan did not want to compete with our insatiable appetite for oil.

Answer 9

The same reason we attacked Vietnam and Iraq.

Answer 10

They where attempting to gain control of the Pacific, so they attempted to take Hawaii