Skip to main content

Modern History—What If the Manhattan Project Never Happened?

An obsessive Software Developer who's constantly googling tutorials, solving problems and drinking an unnecessary amount of coffee.

Operation Plumbbob nuclear test at the Nevada Test Site on June 24, 1957

Operation Plumbbob nuclear test at the Nevada Test Site on June 24, 1957

In 1943, the town of Los Alamos, New Mexico was transformed into a military community with some of the world's best scientists. Jointly directed by America physicist J. Robert Oppenheimer and military engineer Gen. Leslie R. Groves, a secret project called "The Manhattan Project" was underway to develop the first nuclear bomb. After the bomb was developed, President Harry Truman had an extremely difficult decision to make. Should he use this new destructive weapon to bring the war to an end or depend on a future allied invasion that could ultimately cost countless American lives? President Truman approved the use of the atomic weapon and on August 6th 1945, it was dropped on the city of Hiroshima. Out of 76,000 buildings, 70,000 of them were destroyed along with 140,000 of the city's inhabitants. President Truman called on Japan to surrender but after no reply from the Japanese, three days later Truman ordered the second bomb to be dropped on Nagasaki instantly killing 70,000 people. By 1950 another 50,000 people were killed due to radiation.

On August 14th, Japan surrendered, bringing about the end of World War 2. The horrific mass casualties of the atom bombs raise questions of whether the destruction of both Hiroshima and Nagasaki were ethical decisions. In President Truman's diary, he states that he told the Sec. of War, Mr. Stimson " to use the bomb so that military objectives, soldiers and sailors were the target and not women and children", but when the bombs were dropped entire cities were leveled, including men, women and children.

Should President Truman have dropped the atomic bombs? What if the Manhattan Project never existed? The following paper will explain the pros and cons of an alternate timeline where the Manhattan Project never happened.

Operation Downfall and the Invasion of Japan

The Japanese soldiers felt it was their duty to be loyal to their Emperor. They lived by the Samurai Bushido warrior code with no fear of death and felt very strong about their beliefs of nationalism. Kamikaze

bombings and Banzai charges were considered honorable suicides and embedded in the minds of many Japanese soldiers. The U.S saw the Japanese as merciless and fanatic due to their effective suicide bombings. Off the coast Okinawa, more than 350 aircraft at a time dove at the allied fleet which severely damaged the carrier Hancock along with many other ships. President Truman himself said "the Japs are savages, ruthless, merciless and fanatic" in his diary.

In April 1945, the Joint Chiefs of Staff issued an air and sea blockade to reduce Japanese air and naval strength in support of a future Allied invasion. On May 28, 1945 General Headquarters of the U.S. Army Forces in the Pacific, sent around the strategic plan Downfall to senior Army and Navy commanders. Downfall was to execute two phases of operations. First Operation Olympic, the invasion of Kyushu, the southern areas of Japan's four main islands. there land and air forces would support the second phase, This was called Operation Coronet. This operation would attack the heartland; the Tokyo area of Honshu.

If Operation downfall happened, it would of been one of the most horrific battles of World War 2. American planners expected the invasion of Japan to be met with desperate ferocity by the Japanese. Unlike the invasion of Germany, which the U.S had seen tens of thousands of Germans surrender rather than fight to the last death, the Japanese soldiers and civilians were ready to fight to the death against an Allied invasion preferring death before being captured. General Marshall suggested that Allied losses could easily have reached 500,000; furthermore, after the war, General of the Army Omar Nelson Bradley "said as high as one million more men would have been needed for the invasion."

Olympic planners anticipated viscous resistance by up to 9,000 kamikazes, the suicide planes which had sunk 36 vessels and damaged another 368 of the Fifth Fleet's ships at Okinawa. Naval planners also expected assaults by midget submarines, suicde boats, amd human torpedoes along with attacks by the Imperial Japanese Navy's few remaining submarines and destroyers.


Japanese advocates of fighting last counted 2,350,000 Japanese forces in the home islands supplemented by 4,000,000 army and navy civilian employees, and a civilian militia of 28,000,000 to be armed with muzzle-loading rifles, bamboo spears, and bows and arrows ready to fight to the death in honor of the Emperor. The Japanese foresaw a possibly invasion and had gotten all the civilians ready to counter the allies with resistance. My opinion is that many more people, especially American soldiers would have perished if it weren't for the bomb, and the last thing U.S. generals would of wanted was an invasion of Japan.

Another outcome that could have happened with the invasion is that after the Soviets invade Japan as an ally of the U.S. and japan was defeated, the Soviets might of wanted to occupy Japan for years to come.Spreading communism into Japan and using it as a puppet state. The outcome could of been similar to what happened to Berlin, a wall separating east and west with one side communist and the other democracy.

For example, the aftermath of the Korean war completely split the country of Korea in half. Till this day it remains divided. North and South was divided by the 38th parallel. The North was controlled by the Democratic Peoples Republic of Korea (PRK), a police state under the dictatorial rule of Communist leader Kim Il Sun, while the South was controlled by The Republic of Korea under President Syngman Rhee. The uneasy tensions between North and South helped fuel the cold war. Perhaps its possible the same could've happened to Japan if the Soviets held part of it? Maybe Japan wouldn't have had the strong economy it has today if it wasn't unified. As we see with the problem in North and South Korea, North Korea is extremely poor and lacks an economy to fully sustain its food shortages but South Korea went through an economic boom over the years and now holds some of the world's top tech companies, such as Samsung and Hyundai.

Atomic Age—Huge Funds Drained by Paranoia

The atomic age brought about advances in different fields, including biomedicine and the use of nuclear power for civilian purposes, but it also brought about a huge mind shift in America and people around the world. Humans now had the power to completely vaporize entire cities along with any of its inhabitants. If a nuclear bomb drops it destroys everything and everyone, this made people fear war with another nuclear armed country.

Fears only deepened during the cold war. Mass amounts of money were poured into research and development of highly sophisticated ways to deliver nuclear ordinance. The announcement of the Soviet Union having a nuclear weapon on August 29, 1949 triggered both countries enter an arms race. Mutual assured destruction (M.A.D.) was a military strategy conceived in the cold war in which the use of nuclear weapons by two countries against each other would result in annihilation of both the attacker and defender.

Scroll to Continue

Nuclear stockpiles of vast quantities were accumulated in a belief that more nukes would serve as a deterrent against countries thinking about using them. No country wanted a nuclear war, but each side wasn't sure of each others' motives.

The ability to hit anywhere on the planet with a nuke came to a reality with the invention of the intercontinental ballistic missile (I.C.B.M.). Developed by Lockheed Martin., the Atlas ICBM was the first operational intercontinental ballistic missile. It went on alert in Oct. 31, 1959 for the United states. The construction costs for more than 1,000 ICBM launch pads, silos, and support facilities, from 1957-1964 was nearly $14 billion dollars. $14 billion dollars spent on weapons that could completely obliterate entire countries, money that probably would've been better spent if it weren't for the nuclear arms race. Eventually intercontinental ballistic missiles were modified to carry multiple warheads, some warheads hundreds of times more powerful than the one dropped on Hiroshima. The belief during the 1950s for the rapid increase in nuclear weapons was that nuclear weapons gave you a "better bang for a buck". Pound for pound they could deliver more destructive power than conventional weapon, therefore being cost-effective. At the time no one took into account the cost of storing nuclear waste or the amount of technical support it would cost for security of the bombs. Nuclear bombs were actually much more expensive to deploy than allot of people took into account.

According to Atomic Audit: The Costs and Consequences of U.S. Nuclear Weapons Since 1940 (Brookings Institution Press, 1998) the estimated minimum incurred costs of U.S. nuclear weapons programs from 1940 - 1996 was around $5.8 trillion dollars (in billions of constant 1996 dollars).

 Includes average projected future-year costs for nuclear weapons dismantlement and fissile materials disposition and environmental remediation and waste mana

Includes average projected future-year costs for nuclear weapons dismantlement and fissile materials disposition and environmental remediation and waste mana

What If a Politically Unstable Country Developed the Bomb and the U.S. Didn't?

An interesting view to look at is if the U.S. had never conceived of developing atomic bombs, but a different country was the only one to have them. Would that country use them as if they were regular conventional weapons? Some countries seem to have more of a militaristic culture than others. Maybe the Soviets would of thought differently about the bombs if they were the only ones who had secretly attained them. Could it be possible that after World War 2, the Soviets could of just simply gave them to Kim Il Sun during the Korean war to repel the U.S. backed South Koreans? The amount of power a single country would have being the only nuclear force would be a scary thought if the power was in the wrong hands.


I believe the creation of the Manhattan Project, development of the atomic bombs and the decision to use the atomic bombs on Japan definitely affected the worlds course in history. If the U.S. didn't stop Japan with some kind of stunning blow they wouldn't have surrendered. The Japanese commanders feared giving up and saw it as a form of embarrassment. As gruesome as the bombs were, if you look back to how the Japanese were readying their civilians to resist the allied invasion, more than a million people probably would've died, but instead around 250,000 perished in Hiroshima and Nagasaki. The trillions of dollars the United States has spent on nuclear armaments over the years could have been better spent on funding programs to raise global awareness of the threat of nuclear technology. Stronger acts of diplomacy should of been exercised by either the U.N., the U.S. or the Soviet Union, but given the time frame and sudden surprise of the new destructive weapon, it's understandable that the atomic age had brought uncertainty and fear into the world.


pg 141 Contemporary World History by William J. Duiker

Truman quoted in Robert H. Ferrell, Off the Record: The Private Papers of Harry S. Truman (New York: Harper and Row, 1980) pp. 55-56. Truman's writings are in the public domain.

Bushido: The Warrior's Code by Inazo Nitobe

Truman quoted in Robert H. Ferrell, Off the Record: The Private Papers of Harry S. Truman (New York: Harper and Row, 1980) pp. 55-56. Truman's writings are in the public domain.

Downfall: The Invasion that Never Was. by WAYNE A. SILKETT p.113

Downfall: The Invasion that Never Was. by WAYNE A. SILKETT pg 118

Contemporary World History by William J. Dukier pg.239 Official website of Lockheed Martin Nuclear Weapons Cost Study Project

© 2019 Derek Medina

Related Articles