To go into the complete history of atomic and nuclear weaponry would take much longer than I want to discuss here, but to sum it up, the first steps towards developing what would become the atomic bomb were discovered in Europe in 1939. The scientists were mostly German, some of whom were already planning to flee the Nazi regime that had taken over the country six years before.
On 6 December 1941, one day before the Japanese would bomb Pearl Harbor, the United States government and other top scientists formally came together to begin researching atomic development of all kinds.
Over the next few years, a large selection of scientists from across the United States, and other countries, would gather at remote locations across the United States, before eventually making their way to a secret base in Los Alamos, New Mexico. Their goal was to figure out how to turn these new ideas (like the newly discovered process of fission) into weapons. These weapons were initially thought up as a way to fight the Nazi Regime, but the Nazis had already been defeated by the time the bombs were developed and ready to be deployed--which is why they were used against the Japanese Empire instead.
The group of scientists and military personnel working on this project dubbed it "The Manhattan Project," as a code name to keep it secret. The Project would eventually include over 100,000 people and a budget of $2 Billion, so it wasn't really the best kept secret in the world, but the project participants were able to keep the vast majority of details under wraps.
Back over in Europe, the Nazis had also been hoping to create their own atomic weapons, but the Nazi scientists were ultimately unable to create such weapons. Instead, the Nazis focused on their rocket programs, which decimated parts of Europe and the UK. The scientists who worked on Nazi rocket programs were later divided up and brought to the US and the USSR both--which led to the Space Race. That's a whole other tangent we won't be going down today though, but if you are interested in learning more you can read about Operation Paperclip by clicking here.
On 12 April 1945, US President Franklin Roosevelt died. His Vice President was Harry Truman, who assumed the office of President after Roosevelt's death. One of the first things he was briefed on was the Manhattan Project, which he had been completely unaware of before Roosevelt's death.
That must have been a shock.
The Nazis surrendered and ended the war in Europe literally only a few days later, at the end of April, but the Japanese were refusing to surrender and the war in the Pacific raged on. Various campaigns that year, including the battles of Iwa Jima and Okinawa, proved just how bloodthirsty and ferocious the Japanese military were--and just how deadly an invasion of the Japanese mainland would be. As a result, the Manhattan Project was directed to continue their work towards creating a viable atomic bomb.
In the early morning hours of 16 July 1945, the world's first atomic bomb, named "Gadget" was detonated at a site near Alamogordo (now White Sands Missile Range) in New Mexico. The site was nicknamed "Trinity" by J Robert Oppenheimer, and the blast itself, while a success, produced a surprise side effect; green glass created from the massive heat melting the sand beneath the bomb. This green glass is called trinitite today, and can be extremely radioactive.
When Gadget was detonated, the flash produced by the bomb was so bright it could be seen up to ten miles away, and the mushroom cloud created by the blast rose to 40,000 feet! Windows up to 125 miles away were shattered by the force of the blast. It also created a crater a half mile in diameter and twenty-five feet deep. At the bottom of this crater is where the trinitite was created.
Obviously the general public took notice, considering the ground shook like an earthquake as well. The army, knowing they needed to cover up what caused the actual explosion, released the following statement to the press:
“A remotely located ammunition magazine containing a considerable amount of high explosives and pyrotechnics exploded, but there was no loss of life or limb to anyone.”
On July 26th, President Truman, UK Prime Minister Winston Churchill, and Soviet Premier Josef Stalin were meeting at Potsdam in Germany to discuss the ending of the war. Truman informed the other two that the US had a new weapon, the likes of which had never been seen before.
With that knowledge in mind, the Big Three, as they were dubbed, issued an ultimatum to the Japanese Empire--surrender now or face "prompt and utter destruction." The Japanese issued no response, and the war dragged on. By then, it is estimated over 300,000 Japanese civilians had been killed during the war--and yet the Japanese military leaders seemingly didn't care. Instead of preparing to surrender, the military had instead deployed an estimated 560,000 soldiers, boats, and planes to Kyushu Island to fight back the Allied landing force they were expecting. Reports also reached the United States that the Japanese were fully intending to execute all American prisoners being held by the Japanese in the event of an American invasion.
From the National World War II Museum:
By comparison, US forces suffered 49,000 casualties, including 12,000 men killed in action, when facing less than 120,000 Japanese soldiers during the battle for the island of Okinawa from April to June of 1945. At least 110,000 Japanese soldiers and more than 100,000 Okinawan civilians, a third of the island’s prewar population, also perished in the campaign.
It was decided that the new atomic bombs would be used to force the Japanese to surrender. The American government did not question if the bombs should be used--their only question was when and where, specifically because of the ferocity and bloodthirstiness of the Japanese military. Thousands more soldiers from the US, Japan, and China were dying with each passing day the war continued, and Japan had no intention of stopping--even if it meant the majority of their own civilians were killed. While some in the Manhattan Project voted to have a demonstration blast take place near to Japan in the Pacific, this was quickly vetoed after it was decided that a demonstration would not be enough to get the Japanese to surrender.
By August 2nd, the two bombs selected to be deployed against the Japanese had arrived at the US airbase on Tinian Island. During this time, the US military was also considering which two cities would be targeted by the bombs. Initially Kyoto was at the top of the list to be targeted, but was eventually removed after American military leaders appealed to President Truman to protect the ancient capital for its cultural significance. With Kyoto safely out of the way, it was eventually decided that Hiroshima (a large military city with close urban areas and the headquarters of the military planning the large formation of soldiers on Kyushu) and Nagasaki would be the intended targets.
Editor's Note: Throughout the course of the war, the US military would drop paper leaflets all across the Japanese mainland to inform civilians of their intent to bomb certain areas, as a way to help minimize civilian casualties. Before either atomic bomb were dropped, the US created a special new leaflet, known today as the "LeMay Leaflet", that warned the Japanese public of a new and terrifying bomb, stronger than anything anyone had ever seen before. While it is unclear whether or not the pamphlets reached Hiroshima or Nagasaki in time, I feel it should be noted that the United States did in fact make efforts to try and protect civilians. The exact wording of the leaflet can be read by clicking here.
Just after eight AM local time, on 6 August 1945, an American bombing crew dropped the atomic bomb nicknamed "Little Boy" over the city of Hiroshima from an altitude of 31,000 feet. The bomb itself weighed around 10,000 pounds. Forty-five seconds later, the bomb had dropped to 1,900 feet (a distance of around six miles) and detonated directly over a medical building (one source said hospital and another said surgical clinic). Within moments, the temperature below the bomb had reached 12,600° Fahrenheit, or 7,000° Celsius. It is estimated that between 70,000 and 80,000 people were killed instantly, and by the end of the year the death toll had surpassed 100,000. Before the blast, Hiroshima's population was anywhere from 343,000 to 550,000 (sources differ)--so almost a third to a fifth of the people died within four months of the bomb being dropped. Two-thirds of the city's urban areas were destroyed, and the mushroom cloud created by the bomb was visible up to 400 miles away from the blast site.
According to Encyclopedia Britannica:
"The bomb destroyed 26 of the 33 modern firefighting stations in Hiroshima, killing or severely injuring three-fourths of the firefighting personnel. Of 298 registered physicians, only 30 escaped injury and were able to care for survivors. More than 1,800 of the city’s 2,400 nurses and orderlies were killed or seriously injured. Every hospital except one was destroyed or badly damaged. Electric power plants, railroads, telephones, and telegraph lines were all out of commission."
In the immediate aftermath of the bombing, the Japanese military was divided on what their response should be. Some wanted to surrender immediately, while others negotiated that the bomb dropped on Hiroshima was the only atomic bomb in the United State's arsenal, so the war should continue.
Two days later, on 8 August, after a surrender failed to appear, the Soviet Union formally declared war on Japan, adding pressure by invading Manchuria and Sakhalin Island. And yet, the Japanese still refused to surrender.
The following day, an American B-29 bomber loaded with another atomic bomb, this one named Fat Man, proceeded towards Kokura, a Japanese city with a massive military arsenal, on the aforementioned island of Kyushu. However, cloudy weather that morning made it impossible for the American airmen to see their target, and so the decision was made to proceed to the secondary target, Nagasaki.
When the B29 reached Nagasaki however, the cloud cover was even thicker than it had been over Kokura. With fuel running low, the airmen made the decision to drop the bomb almost blind, and far from the original intended drop point. At 11:02 AM, Fat Man detonated at an altitude of 1,650 feet. The Fat Man blast was 40 percent more powerful than that detonated over Hiroshima, and an estimated 40,000 people were killed instantly, and by year's end, another 30,000 would also succumb. Luckily several thousand civilians, including school children, had been evacuated from the city before the bomb dropped.
As for the city itself, around 40 percent of Nagasaki's buildings were destroyed, but because of its unique geographic surrounded by multiple hills, large sections of the city were relatively unscathed, in sharp contrast to Hiroshima.
The bombing of Nagasaki finally forced the Japanese to surrender, and the Emperor formally declared their intention to do so on August 10th. In their surrender documents, the Japanese declared they would only do so if the emperor would be allowed to remain the sovereign head of Japan.
The Americans flatly rejected this proposal, and their exact response was:
“From the moment of surrender the authority of the Emperor and the Japanese Government to rule the state shall be subject to the Supreme Commander of the Allied Powers who will take such steps as he deems proper to effectuate the surrender terms.”
At the same time as this declaration, President Truman was informed another atomic bomb would be ready to be shipped to the Pacific front in a matter of days. Back in Japan, certain members of the military attempted a coup, but this effort failed. On August 14th, the Japanese surrendered, accepting the Allied terms. The next day, a pre-recorded message from the emperor would be played on Japanese radio, allowing the vast majority of the citizens to hear their emperor's voice for the first time.
The war would officially end on 2 September 1945, when surrender documents were formally signed.
On 30 June 1946, the United States War Department would publicly publish the findings they had conducted in Nagasaki and Hiroshima after the hostilities had ceased the year before. Data had been compiled by members of the Manhattan Project, and sourced from the United States, Great Britain, and Japan. The findings concluded that in Hiroshima, 135,000 had died, and another 64,000 in Nagasaki. It is important to note, however, that the report is most likely underreporting the death toll. At the time of the bombings, forced laborers imported from Korea were present, numbering in the thousands, in both cities. How many of them died was unknown, seeing as the Japanese themselves had no idea how many of these prisoners were being held in Hiroshima and Nagasaki. The commission also concluded that the deaths and injuries caused to humans as a result of the bombs could fall into three categories: burns, radiation injuries, and mechanical injuries.
From Encyclopedia Britannica:
Burns caused about 60 percent of the deaths in Hiroshima and about 80 percent in Nagasaki. Falling debris and flying glass caused 30 percent of the deaths in Hiroshima and 14 percent in Nagasaki. Radiation caused 10 percent of the deaths in Hiroshima and 6 percent in Nagasaki. No harmful amount of persistent radioactivity was found in either of the two cities in the months after the bombings.
After the conclusion of hostilities, the United States occupied much of Japan, and as a result, also helped begin the rebuilding efforts in Nagasaki and Hiroshima both. Almost immediately, both cities became cultural hubs to bring awareness to the destructive properties of atomic bombs, as well as the peace initiatives to ensure they are never used again.
All Japanese citizens who survived the bombings were offered free medical care, for life, by the Japanese government. A commission was also set up to research the effects of radiation on human beings, and over 120,000 survivors signed up for their lifelong program, allowing a huge pool of resources to be added to the data set.
As previously mentioned, the Japanese military was especially brutal. The leaders of the armed forces didn't care how many soldiers and civilians were killed during the war. All that mattered was that they won--and didn't suffer the humiliation and shame of losing.
By the time the bombs were dropped, Emperor Hirohito was ready to surrender to the Allies, but his military would not let him.
Operational Downfall, the Allied plan to invade the Japanese mainland, was estimating the number of people killed in the endeavor could enter the millions, and drag the war into yet another year--going through at least the spring of 1946.
While most people see the start of World War II as being in 1939, when Hitler invaded Poland, I personally push that date back further to 1937. In 1937, Japan invaded the Chinese mainland, and soon after undertook what has been dubbed the Rape of Nanking, where Japanese soldiers raped thousands of Chinese women and killed thousands more civilians, including children. Some in Japan deny this event after happened, despite the overwhelming evidence and stories of survivors like Minnie Vautrin.
Whichever date you choose to look at, this war had been dragging on anywhere from nine to eleven years. Millions of people were dead, and millions more would likely be killed if Operation Downfall were put into place. Japan was not about to surrender without a massive fight.
After the bombings, once Japan finally surrendered, the Allied Powers immediately set to work forming the Tokyo War Crimes trial. Twenty-eight Japanese officials from the military and government were arrested and tried for the crimes they committed during the war. Sixteen defendants were eventually sentenced to life imprisonment, while seven more were sentenced to death by hanging. Eleven allied countries came together to oversee the trials, which lasted until1948.
The prosecution had to prove the defendants not only knowingly committed war crimes or oversaw soldiers who did, but that they also had the ability to stop the crimes from being committed and chose not to. The defense argued one of the oldest defenses in the world--self defense.
(I'm sorry I'm really trying to not show my bias here, but HOW can you claim self defense when YOU invaded someone else, i.e. China. HOW?!)
Of the twenty-eight defendants initially arrested: one was released after being deemed mentally unfit to stand trial, two died of natural causes during the trial, seven were sentenced to death, and sixteen were sentenced to life in prison. However, of those sixteen, three died in prison while the rest were paroled between 1954 and 1956.
After the initial trials ended, another 5,500 or so lower-ranking Japanese people were tried for war crimes as well, with the final trial taking place in 1951.
According to the National World War II Museum, multiple countries conducted multiple trials, and of those countries they sentenced multiple Japanese people to death for their crimes. The list reads in total:
United States - 140
The Netherlands - 236
United Kingdom - 223
Australia - 153
China - 149
France - 26
Philippines - 17
Or a total of 950 people (including the six from the first set of trials). For context, the Japanese military murdered anywhere from 100,000 to 300,000 people in Nanking, China in only a few short weeks.
Other atrocities committed by the Japanese military included on at least three separate occasions, after a Japanese submarine sank US ships, they would then attack the lifeboats the United States survivors had made it into. Japanese treatment of POWs as a whole, regardless of nationality, were absolutely brutal and horrific, but one of the worst known incidents is known as the Bataan Death March.
In 1942, as the Japanese continued to occupy the Philippines, the Japanese military forced 76,000 POWs to march sixty-six miles through the jungle, before being then forced onto train cars, driven by rail further north on the island with up to 100 men standing in a boxcar meant for forty or less, and then forced to march another seven miles. During the march, prisoners were stabbed with bayonets, beaten, beheaded, and many of those who did survive the march itself died of starvation and disease. Some grew so weak during the march they were unable to rise from the ground come morning, and when this happened they were often buried alive or beaten to death with shovels. It is believed of the original 76,000, around 22,000 died. Those that survived were shipped all around the Philippine Islands to work as forced laborers for the Japanese. It is estimated that American POWs held by the Japanese during this time had a death rate of a bit more than 30%, as opposed to a death rate of 3% at the hands of other Axis Powers like the Nazis (another source states the numbers were closer to 35% from the Japanese and 0.9% from the Nazis).
The Japanese also worked thousands of other POWs from The Netherlands, Australia, and Great Britain to death in their forced labor camps, though those stories are less well-known today, much like many of the other stories I am about to tell you.
There was also Unit 731, a secret branch of the Japanese military that conducted horrific medical experiments on prisoners of war from China, Russia, Korea, and Mongolia. After the end of the war, the unit destroyed the majority of their documents so the true nature of their crimes is mostly shrouded in mystery today. What is known is that subjects were forcibly infected with various diseases to see how the human body would react to them. This could be anything from having rats carrying the plague biting prisoners, to forcing male prisoners who had syphilis to rape male and female prisoners alike to see how the syphilis would move and infect another host. The women who fell pregnant from these attacks were studied to see how syphilis developed in their babies--and sometimes the "doctors" would surgically cut open the women to see how the fetus was developing. Thousands of innocent people were killed as a result of the torture.
By the way, Japan refused to even acknowledge Unit 731 was a real organization until 1988, but that acknowledgement came with NO apology (and as of 2025, the Japanese government still has issued no apology). Six years previously, after decades of frustration, the Chinese government had taken it upon themselves to shed light on these experiments by opening a museum to teach the world about Unit 731. The museum was opened in the same location the experiments had once taken place in China.
During the war crimes trials that had taken place after the war, not a single member of Unit 731 was put on trial. No one was ever even formally accused of a crime, much less convicted of one. General Douglas MacArthur from the United States had decided that the information gathered by Unit 731 was too beneficial to give up, and so he granted immunity to the unit's medical staff in order to obtain the information they had learned during their so-called experiments.
And if all that is not bad enough, tens of thousands of Korean and Taiwanese women were forced into prostitution by the Japanese military as well. These young women and girls were called "Comfort Women," and some were as young as fifteen when they were kidnapped from their homes and shipped to occupied-China to work in brothels for the Japanese military. Sadly, for the women who survived the years of brutal treatment, things didn't improve much when they got home. Many Korean families shunned their female relations who had been kidnapped and tortured, claiming they brought shame on the family.
Japan had occupied Korea in 1910, and the Korean people would not be free of Japan until the war's end. While technically Japan has "apologized" for their treatment of Korean women during the war, and even doled out reparations decades after the fact, for the majority of Korean people today it is too little too late, and anti-Japanese hostility is still fairly common. At what point, the former Japanese Prime Minister Shinzo Abe (who was assassinated in 2022) was even considering "revising" the apology made to South Korea because he thought anti-Japanese sentiment was getting to be too high. While some parts of the Comfort Women story have been challenged by historians, the true truth of the matter lays buried and probably always will.
Another aspect of the war that is rarely covered is "Ketsu Go"--a Japanese thought process that allowed the US military to proclaim at one point, "There are no civilians in Japan."
In March of 1945, Japan decided to muster into service every male citizen between the ages of fifteen and sixty, and every female citizen between the ages of seventeen and forty. This immediately added an estimated eighteen to twenty million people (around a quarter of the total population) into military service, many of whom were already in Kyushu (as previously mentioned). While the government had no uniforms to provide these new recruits, they were very much seen as part of the armed forces. This also played into what the Japanese government wanted anyway--to make combatants and actual civilians indistinguishable to the Allied Forces. And it went beyond adults. There are surviving photos showing elementary school children on the lawns of their schools fighting with wooden sticks they had sharpened themselves! A simple Google Image search result can pull them up, or if you don't believe me you can just click here.
And then there's the Yakusini Shrine. While, in essence, the Shinto shrine was officially built as a way to honor the Japanese soldiers who died in war, the controversial aspect of the shrine lies in the fact that it also honors those convicted of war crimes as well. To date, there are over 2.5 million individuals named and honored at the shrine, which dates all the way back to 1869. In 1978, someone secretly added the names of fourteen individuals found guilty at the Tokyo War Trials. The shrine has been vandalized multiple times, and each time the shrine is repaired and if the vandals are caught, they are arrested. Of the two acts of vandalism I read about, both included wording written in a Chinese alphabet.
Today, many Japanese people are confused as to why other neighboring countries are still so angry with them. Part of the problem stems from the fact that the Japanese government conveniently leaves out large swaths of history, like I've described to you here. Much like the Turkish government refusing to acknowledge the Armenian Genocide, the Japanese government rarely mentions their own Twentieth Century atrocities, and when they do, its a vast understatement of what actually occurred. Some leading Japanese historians, who write the country's textbooks and curriculum, purposefully refuse to acknowledge war crimes because they don't see them as such. Nationalism in it of itself is not inherently dangerous, but outright refusing to acknowledge the rape, murder, and torture of thousands of people across several different countries because you view it as "necessary" and that your country "did nothing wrong," is not going to win you any favors either.
I am sure all of you have heard the phrase, "history is written by the victors,"--and Japan was most certainly not a victor in World War II. Today, while horrific tragedies like the Shoah and other atrocities perpetuated by the Nazi Regime are known far and wide, Japanese war crimes are swept under the rug much more often--here in the United States and in Japan.
While none of the war crimes perpetuated by the Japanese military justify the deaths of civilians, I hope that by highlighting some of the horrible things the Japanese Military did help paint a better picture of why dropping the atomic bombs were not just necessary, but the only way to end what was an already terrible war as quickly as possible.
An Indian officer serving with the British is quoted as having written this poem about the Japanese military:
No prisoners we took, no mercy we gave
Their crimes against comrades we never forgave
I know that was a lot of information to unpack, but I always want to paint a full picture of what happened during historical events. I am not saying that the United States or other Allied Powers were entirely innocent either. War crimes were committed against civilians and soldiers alike on all sides, but what I am saying is that there was no mention of any of these other atrocities that led up to the bombs being dropped at the museum in Hiroshima when I visited in June of 2025.
But, since I have brought up the museum again, let me provide some more information on the Peace Gardens and museum itself.
The centerpiece of the Gardens is the A Bomb Dome, which I provided pictures of previously. Immediately after the bombing, it was decided to preserve the dome exactly as it looked after the bomb went off (for the time being anyway, the decision to preserve it indefinitely wasn't made until 1966). In 1950, the Hiroshima government designated it as a historic site in order to help preserve the ruin. The dome itself was then named a UNESCO World Heritage Site in 1996 (despite the United States and China making it known they had "reservations" about the inclusion--what exactly that means I don't know but that's the word Encyclopedia Britannica used!). In 2007, the gardens were further protected by additional Japanese law after being named a "Place For Scenic Beauty."
The museum itself opened in 1955, with additional wings and other aspects continually added to it over the years.
The gardens surrounding the dome are today set aside as a place of prayer as well as a permanent installation of several art pieces (like the Children's memorial I also mentioned above), all created as a form of silent protest against the use of nuclear weapons and to hope that they are never used in warfare again.
Every year on August 6th, a special memorial is held in front of the cenotaph placed in the park.
I don't really know how to end this blog post. We started with photos of cute deer and ended up on a long winded explanation of not only the lead up to dropping the Atomic bombs, but also only a selection of the more infamously known war crimes committed by the Japanese military.
What I have learned about World War II, after my own self reflection, is that really there were no good guys and no bad guys--at least not from the perspective of the governments running the show. One of my grandfathers, one of my great-uncles, two of my great-aunts, and several other relatives besides served in World War II. They saw the horrible tragedies of war up close and personal. I would never dishonor their memory, but what I am saying is that the United States government didn't escape with a clean record either. What I do want better known is just how horrible Japan's record actually was. I want schools to teach the Pacific Theatre on an equal footing as the European, which is far far from the case with American public school systems.
I want the world to see all sides of every aspect of history. I want the world to be more informed about events that happened, during our lifetimes and before. I really wish governments would stop threatening each other with nuclear bombs too, but we all know that's not going to go away anytime soon.
At the end of the day, I want to honor and remember all of the millions of innocent people who were killed on all sides of the conflict, the good, actual, innocent people. And I want to honor those who survived, but came home scarred inside and out as well. That's who really matters at the end of the day.
(But as for the men and women who committed war crimes against their fellow human beings, I hope every single one of them is burning in Hell 😀 ).
