The Empire of Japan entered World War II by launching a surprise offensive which opened with the attack on Pearl Harbor at 7:48 a.m.
Hawaiian Time (18:18 GMT) on December 7, 1941.
Over the course of seven hours there were coordinated Japanese attacks on the U.S.-held Philippines, Guam and Wake Island and on the British Empire in Borneo, Malaya, Singapore, and Hong Kong.
The strategic goals of the offensive were to cripple the U.S. Pacific fleet, capture oil fields in the Dutch East Indies, and maintain their sphere of influence of China, East Asia, and also Korea. It was also to expand the outer reaches of the Japanese Empire to create a formidable defensive perimeter around newly acquired territory.
The decision by Japan to attack the United States remains controversial.
Study groups in Japan had predicted ultimate disaster in a war between Japan and the U.S., and the Japanese economy was already straining to keep up with the demands of the war with China.
However, the U.S. had placed an oil embargo on Japan and Japan felt that the United States' demands of unconditional withdrawal from China and non-aggression pacts with other Pacific powers were unacceptable.
Facing an oil embargo by the United States as well as dwindling domestic reserves, the Japanese government decided to execute a plan developed by the military branch largely led by Osami Nagano and Isoroku Yamamoto to bomb the United States naval base in Hawaii, thereby bringing the United States to World War II on the side of the Allies.
On September 4, 1941, the Japanese Cabinet met to consider the war plans prepared by Imperial General Headquarters, and decided:
Our Empire, for the purpose of self-defense and self-preservation, will complete preparations for war ... [and is] ... resolved to go to war with the United States, Great Britain, and the Netherlands if necessary.
Our Empire will concurrently take all possible diplomatic measures vis-a-vis the United States and Great Britain, and thereby endeavor to obtain our objectives ... In the event that there is no prospect of our demands being met by the first ten days of October through the diplomatic negotiations mentioned above, we will immediately decide to commence hostilities against the United States, Britain and the Netherlands.
The Vice Admiral Isoroku Yamamoto, the chief architect of the attack on Pearl Harbor, had strong misgivings about war with the United States.
Yamamoto had spent time in the United States during his youth when he studied as a language student at Harvard University (1919–1921) and later served as assistant naval attaché in Washington, D.C. Understanding the inherent dangers of war with the United States, Yamamoto warned his fellow countrymen:
"We can run wild for six months or maybe a year, but after that, I have utterly no confidence he Imperial Japanese Navy made its surprise attack on Pearl Harbor, Oahu, Hawaii Territory, on Sunday morning, December 7, 1941.
The Pacific Fleet of the United States Navy and its defending Army Air Forces and Marine air forces sustained significant losses.
The primary objective of the attack was to incapacitate the United States long enough for Japan to establish its long-planned Southeast Asian empire and defensible buffer zones.
However, as Admiral Yamamoto feared, the attack produced little lasting damage to the US Navy with priority targets like the Pacific Fleet's three aircraft carriers out at sea and vital shore facilities, whose destruction could have crippled the fleet on their own, were ignored. Of more serious consequences, the U.S. public saw the attack as a barbaric and treacherous act and rallied against the Empire of Japan.
The United States entered the European Theatre and Pacific Theater in full force.
Four days later, Adolf Hitler of Germany, and Benito Mussolini of Italy declared war on the United States, merging the separate conflicts. Following the attack on Pearl Harbor, the Japanese launched offensives against Allied forces in East and Southeast Asia, with simultaneous attacks on British Hong Kong,
British Malaya and the Philippines. By the time World War II was in full swing, Japan had the most interest in using biological warfare.
Japan's Air Force dropped massive amounts of ceramic bombs filled with bubonic plague-infested fleas in Ningbo, China.
These attacks would eventually lead to thousands of deaths years after the war would end.
In Japan's relentless and indiscriminate research methods on biological warfare, they poisoned more than 1,000 Chinese village wells to study cholera and typhus outbreaks.
These diseases are caused by bacteria that with today's technology could potentially be weaponized.
A map of the Canterbury in New Zealand prepared by the Japanese Military following the attack on Pearl Harbour South-East Asia Main articles: South-East Asian theatre of World War II and South West Pacific theatre of World War II The South-East Asian campaign was preceded by years of propaganda and espionage activities carried out in the region by the Japanese Empire.
The Japanese espoused their vision of a Greater Asian Co-Prosperity Sphere, and an Asia for Asians to the people of Southeast Asia, who had lived under European rule for generations.
As a result, many inhabitants in some of the colonies (particularly Indonesia) actually sided with the Japanese invaders for anti-colonial reasons.
However, the ethnic Chinese, who had witnessed the effects of Japanese occupation in their homeland, did not side with the Japanese.
Japanese troops march through the streets of Labuan, Borneo in January 14, 1942. Hong Kong surrendered to the Japanese on December 25. In Malaya the Japanese overwhelmed an Allied army composed of British, Indian, Australian and Malay forces.
The Japanese were quickly able to advance down the Malayan Peninsula, forcing the Allied forces to retreat towards Singapore.
The Allies lacked air cover and tanks; the Japanese had air supremacy. The sinking of HMS Prince of Wales and HMS Repulse on December 10, 1941, led to the east coast of Malaya being exposed to Japanese landings and the elimination of British naval power in the area.
By the end of January 1942, the last Allied forces crossed the strait of Johore and into Singapore.
In the Philippines, the Japanese pushed the combined Filipino-American force towards the Bataan Peninsula and later the island of Corregidor.
By January 1942, General Douglas MacArthur and President Manuel L. Quezon were forced to flee in the face of Japanese advance.
This marked among one of the worst defeats suffered by the Americans, leaving over 70,000 American and Filipino prisoners of war in the custody of the Japanese. Battle of Singapore, February 1942.
Victorious Japanese troops march through the city center. (Photo from Imperial War Museum) On February 15, 1942, Singapore, due to the overwhelming superiority of Japanese forces and encirclement tactics, fell to the Japanese, causing the largest surrender of British-led military personnel in history.
An estimated 80,000 Indian, Australian and British troops were taken as prisoners of war, joining 50,000 taken in the Japanese invasion of Malaya (modern day Malaysia).
Many were later used as forced labour constructing the Burma Railway, the site of the infamous Bridge on the River Kwai. Immediately following their invasion of British Malaya, the Japanese military carried out a purge of the Chinese population in Malaya and Singapore.
The Japanese then seized the key oil production zones of Borneo, Central Java, Malang, Cepu, Sumatra, and Dutch New Guinea of the late Dutch East Indies, defeating the Dutch forces.
However, Allied sabotage had made it difficult for the Japanese to restore oil production to its pre-war peak.
The Japanese then consolidated their lines of supply through capturing key islands of the Pacific, including Guadalcanal. Tide turns (1942–45) Battle of Midway.
The attack by dive bombers from USS Yorktown and USS Enterprise on the Japanese aircraft carriers Soryu, Akagi and Kaga in the morning of 4 June 1942.
Japanese military strategists were keenly aware of the unfavorable discrepancy between the industrial potential of the Japanese Empire and that of the United States.
Because of this they reasoned that Japanese success hinged on their ability to extend the strategic advantage gained at Pearl Harbor with additional rapid strategic victories.
The Japanese Command reasoned that only decisive destruction of the United States' Pacific Fleet and conquest of its remote outposts would ensure that the Japanese Empire would not be overwhelmed by America's industrial might.
In April 1942, Japan was bombed for the first time in the Doolittle Raid.
In May 1942, failure to decisively defeat the Allies at the Battle of the Coral Sea, in spite of Japanese numerical superiority, equated to a strategic defeat for Imperial Japan.
This setback was followed in June 1942 by the catastrophic loss of four fleet carriers at the Battle of Midway, the first decisive defeat for the Imperial Japanese Navy.
It proved to be the turning point of the war as the Navy lost its offensive strategic capability and never managed to reconstruct the "'critical mass' of both large numbers of carriers and well-trained air groups".
Australian land forces defeated Japanese Marines in New Guinea at the Battle of Milne Bay in September 1942, which was the first land defeat suffered by the Japanese in the Pacific.
Further victories by the Allies at Guadalcanal in September 1942, and New Guinea in 1943 put the Empire of Japan on the defensive for the remainder of the war, with Guadalcanal in particular sapping their already-limited oil supplies.
During 1943 and 1944, Allied forces, backed by the industrial might and vast raw material resources of the United States, advanced steadily towards Japan.
The Sixth United States Army, led by General MacArthur, landed on Leyte on October 20, 1944. In the subsequent months, during the Philippines Campaign (1944–45), the combined United States forces, together with the native guerrilla units, liberated the Philippines.
By 1944, the Allies had seized or bypassed and neutralized many of Japan's strategic bases through amphibious landings and bombardment.
This, coupled with the losses inflicted by Allied submarines on Japanese shipping routes began to strangle Japan's economy and undermine its ability to supply its army.
By early 1945, the U.S. Marines had wrested control of the Ogasawara Islands in several hard-fought battles such as the Battle of Iwo Jima, marking the beginning of the fall of the islands of Japan.
Air raids on Japan Main article: Air raids on Japan The atomic bombing of Nagasaki on August 9, 1945 After securing airfields in Saipan and Guam in the summer of 1944, the United States Army Air Forces undertook an intense strategic bombing campaign, using incendiary bombs, burning Japanese cities in an effort to pulverize Japan's industry and shatter its morale.
The Operation Meetinghouse raid on Tokyo on the night of March 9–10, 1945, led to the deaths of approximately 100,000 civilians.
Approximately 350,000–500,000 civilians died in 66 other Japanese cities as a result of the incendiary bombing campaign on Japan.
Concurrent to these attacks, Japan's vital coastal shipping operations were severely hampered with extensive aerial mining by the U.S.'s Operation Starvation.
Regardless, these efforts did not succeed in persuading the Japanese military to surrender.
In mid-August 1945, the United States dropped nuclear weapons on the Japanese cities of Hiroshima and Nagasaki.
These atomic bombings were the first and only used against another nation in warfare.
These two bombs killed approximately 120,000 to 140,000 people in a matter of minutes, and as many as a result of nuclear radiation in the following weeks, months and years.
The bombs killed as many as 140,000 people in Hiroshima and 80,000 in Nagasaki by the end of 1945,Takashi (one of the survivals) said describing the situation at this time when he was a kid: beneath the heap I lay buried on my back unable to move one of the soldiers saved me, he was carrying me weaved in and out the throngs of people who were screaming in agony charred or just barely alive, creeping, stumbling, dragging their feet looking for any escape from the blazing inferno.