In 1939, the President of the USA, FDR, was informed by US intelligence that Germany was on her way to making a nuclear bomb of their own. This led to the creation of the Advisory Committee on Uranium, a team tasked with harnessing and weaponising uranium. Based upon the committee’s findings, the US started funding research by Enrico Fermi and Leo Szilard, which was focused on uranium enrichment and nuclear chain reactions. The name was changed to the National Defence Research Committee in 1940 and finally the Office of Scientific Research and Development (OSRD) in 1941. In the same year, following the Pearl Harbour attack, the US entered WWII on the side of the Allied powers to fight the Axis. The Army Corps of Engineers merged with the OSRD with FDR’s approval, and the project morphed into a military initiative with scientists playing a supporting role. The OSRD created the Manhattan Engineering District in 1942, basing it in NYC U.S Army Colonel Leslie R. Groves was appointed to lead the project. Fermi and Szilard successfully enriched uranium for the production of uranium-235, for use in the bombs. On December 28th, 1942, FDR approved the formation of the Manhattan project to combine these research efforts with the goal of weaponising nuclear energy. Remote research facilities are set up in Washington, New Mexico and Tennessee as well as sites in Canada, for these tests to be performed. Robert J. Oppenheimer was named Director of the Los Alamos Laboratory in northern New Mexico in 1943. He was already working on the concept of fission energy alongside Edward Teller and others. The Los Alamos Laboratory, the creation of which was named Project Y, was formally established on January 1st, 1943. The complex would be the site of testing of the bombs. On July 26, 1945, in a remote desert location near Alamogordo, NM, the first atomic bom was successfully detonated.
The Japanese had bombed Pearl Harbour one of the United States’ most important naval bases, this move was a surprise attack from the Japanese as rising tensions between the two nations from Japan’s global expansion towards the east Asian countries meant that conflict was inevitable. This led to america's immediate retaliation towards the Japanese
According to Charles Maier, a history professor at Harvard university. After the surrender of Nazi Germany, the Japanese would still not agree to an unconditional surrender. There was an option to invade Japan (Operation Downfall) but that would be very costly so the American president Truman was convinced he had no other choice and that other ways to get Japan to surrender would’ve resulted in up to 10 million Japanese lives lost.
The Americans wanted the war to end before the Soviet Union could enter Japan, in a different scenario if Truman had decided to put off the atom bomb option. The war would’ve ended, with herculean levels of bloodshed, then at some point in 1946 Truman would've revealed the existence of the bomb to the grieving American public, and the president of the United States would have to explain to thousands of grieving family members and wounded service men that he decided not use it because he thought it was too cruel to drop on the enemy, even after a surprise assault, a global war fuelled endeavours of global dominated, hundreds of thousands of Americans killed and wounded in two scenarios, and years of gruesome firebombing.This would've unquestionably lead to the impeachment of Truman
The US had brilliant minds like the Theoretical physicist Albert Einstein with his innovative research and his equation (E=mc2) which accelerated research into the bomb and the ‘father of the atomic bomb’ J. Robert Oppenheimer another theoretical physicist who led the scientific end of the secret Manhattan project to manufacture the first atomic bomb.
After successfully refining the atomic bomb in the Manhattan project, the US tested the first Atomic Bomb successfully in the “Trinity” test site in New Mexico two days after the Nazi Germany surrender.
On August 6th, 1945, after the green light from Truman, the B-29 bomber ‘Enola Gay’ deployed the uranium-core bomb, the Little Boy. It detonated 1828.8 m above Hiroshima and instantly incinerated 80,000 people and devastated most of the city.
3 days later, August 9th, Little Boy is dropped on Nagasaki, killing an estimated 75% of people immediately and 60-70% of the city laid in ruins.
Hiroshima was chosen for it's opportunity to be studied on for the effects on an atomic bomb on a city and the city had not been targeted by any US forces beforehand, not to also mention it's military significance
The original target for the 2nd bomb was Kokura, a city which produced munitions for the war. But due to heavy cloud cover, the bomber diverted to the back-up target that was Nagasaki, and dropped the bomb into a valley, sparing much of the city, but still devastating it.
Operation Downfall was the codename given for the Allied invasion of mainland Japan.
Operation Olympic would capture the Southern Island, using the recently captured island of Okinawa as a jumping-off point for the invasion. This would happen in November 1945.
In early 1946, Operation Coronet would commence, and it would capture the Kanto Plain, East of Tokyo. The airbases captured in Kyushu would provide land-based air support to the troops that would storm the plain.
Held near Berlin, from July 17-August 2, 1945, it was mainly addressing problems in Europe but this led to discussions of a Japanese surrender.
On July the 26th, 1945, Truman, Churchill and Chiang Kai-Shek issued the document that outlined the terms of surrender for Japan. The ultimatum stated that, if Japan did not surrender immediately, it would face “prompt and utter destruction”.
The terms of the declaration for Japan were specified as:
The elimination 'for all time of the authority and influence of those who have deceived and misled the people of Japan into embarking on world conquest', The occupation of 'points in Japanese territory to be designated by the Allies'
That the 'Japanese sovereignty shall be limited to the islands of Honshu, Hokkaido, Kyushu, Shikoku, and such minor islands as we determine,' as had been announced in the Cairo Declaration in 1943
That 'the Japanese military forces, after being completely disarmed, shall be permitted to return to their homes with the opportunity to lead peaceful and productive lives'
That 'we do not intend that the Japanese shall be enslaved as a race or destroyed as a nation, but stern justice shall be meted out to all war criminals, including those who have visited cruelties upon our prisoners'
“The Japanese Government shall remove all obstacles to the revival and strengthening of democratic tendencies among the Japanese people. Freedom of speech, of religion, and of thought, as well as respect for the fundamental human rights shall be established.'
'Japan shall be permitted to maintain such industries as will sustain her economy and permit the exaction of just reparations in kind, but not those which would enable her to rearm for war. To this end, access to, as distinguished from control of, raw materials shall be permitted. Eventual Japanese participation in world trade relations shall be permitted.'
'The occupying forces of the Allies shall be withdrawn from Japan as soon as these objectives have been accomplished and there has been established, in accordance with the freely expressed will of the Japanese people, a peacefully inclined and responsible government.'
The Japanese rejected these demands, and reaped the consequences for it with the bombs in August
What immediate and post war effects did the bombs have on Hiroshima and Nagasaki and the rest of the world?
The immediate effects of both bombs saw the deaths, between between 90,000 and 146,000 people in Hiroshima and 39,000 and to 80 000 Nagasaki by the end of 1945 with roughly half off the deaths occur in both cities on just the first day.
In Hiroshima and Nagasaki, most victims died without any anaesthetic or pain killer. Some of those support workers who entered the city also passed away from devastating radiation. 10 years later more victims began suffering from thyroid, breast, lung and other cancers at far higher rates than what was previously recorded
In Hiroshima 90 per cent of physicians and nurses were killed or injured; 42 of 45 hospitals were rendered useless; and 70% of victims had combined injuries, in most cases, severe burns to skin. For solid cancers, the added risk relating to radiation exposure continued to increase throughout the lifespan of survivors even today, 75 years after the attacks.
70% of all buildings in Hiroshima were ravaged to the ground, and 6.7 km2 of Nagasaki was completely levelled. Pregnant women exposed to the bombs experienced higher rates of miscarriage and deaths amongst their infants.
Increased rates of cancer and chronic disease were also recorded amongst the survivors. Newborns exposed to the radiation from while in the womb had higher rates of intellectual abnormalities and stunted growth, as well as a much higher risk of developing every single kind of cancer known to man.
In Hiroshima, everything in a 4.4-mile radius of the detonation was obliterated.
The bomb had the effect of 20,000 tons of TNT. Surviving animals and humans in the city sustained severe burns, sustained radiation and injuries from flying glass.
In Nagasaki, nearby trees were uprooted, snapped off, scorched or stripped of leaves.
Both cities were extensively destroyed over 67 percent of Hiroshima’s structure were destroyed and in Nagasaki nearly everything with 1/2 mile was immediately destroyed
Temperatures at the point of the explosion reached up to 4,000O C
In a diplomatic sense, the bombs effectively ended the war in the Pacific, and thus ended the Second World War. The bombs caused Josef Stalin, the leader of the Soviet Union to ramp up efforts of the USSR’s own bomb project to get their own bomb. This provoked a nuclear arms race, starting after the first Soviet nuclear test, that would last until the collapse of the Union in 1991.
Due to these bombs and the Soviet’s invasion into Japanese controlled, Manchuria that finally persuaded Emperor Hirohito to surrender despite fierce opposition to the decision from military leaders within Japan like Hideki Tojo Japan lost 2.3 million soldiers and an estimated 800,000 civilians in WWII. General Douglas MacArthur, who was made Allied commander, was sent to Japan to oversee its rehabilitation. The country found itself occupied for years by the United States, who introduced democratic reforms.
While many wanted Hirohito to be tried as a war criminal, MacArthur made a bargain with the emperor that included the implementation of a new Japanese constitution and the denouncement of imperial 'divinity.' Thus, Hirohito became a democratic figurehead, with the country eventually attaining political stability and becoming an economic leader.
What effects did the bombs have on the rest of the world?
The bombs helped begin the Cold War and the Nuclear Arms Race between the 2 Superpowers after the chaos of WW2: the USA and the USSR.
External sources suggest the bombs were more directed towards the Soviets than Japan, as in, flexing to them of American technological might. However, fact was, the Soviets had known about this from as early as September 1941. Thanks to past endeavours of federal espionage, the Soviets managed to build a bomb of their own just 4 years after the US detonated theirs over Hiroshima and Nagasaki.
Nuclear Weapons played a crucial role in the strategic teachings of both NATO and the Warsaw Pact during the mid-late Cold War years. However, almost all Warsaw Pact guidelines assumed the green light for the usage of “tactical” nukes (bombs with a small warhead), while for NATO, there wasn’t as much of an emphasis on this.
After the events of the cold war, the world was opened to an alarming new time, where any moment the world could quickly be devastated in nuclear war. These days, threat of nuclear war is taken very seriously, as seen with North Korea and the US in their time of tension.
However, thankfully, both the US and Soviet Union saw the use of these weapons as having catastrophic effects on the human race and the world, and as such, they never went to war over such fears.