The Manhattan Project
Why the US joined the race to build a nuclear weapon?
In December 1938, German scientists discovered a startling phenomenon. Uranium, when bombarded with neutrons, turned into Barium, releasing a huge amount of energy. Hungarian physicist Leo Szilard was quick to recognise its importance and created the world’s first nuclear chain reaction. He wrote a letter to President Theodore Roosevelt urging him to accelerate American research in nuclear weapons. In the letter, Szilard forewarned the president of the destruction that the Nazis could wreck if they possessed their own nuclear weapons. The president responded by creating the Advisory Committee on Uranium in 1939, which would eventually establish the ‘Manhattan Engineer District’ (MED). This would subsequently gain popularity as the Manhattan Project.
Despite work having started on the Manhattan Project, it was slow and lacked funding. After Japan attacked Pearl Harbor and US’s official entry into the second world war, it picked up momentum. Julius Robert Oppenheimer was placed as the scientific director and multiple testing laboratories were set up across the country. Los Alamos, in the New Mexico desert, was selected due to its remote location for secrecy and security. He recruited a team of expert scientists from across the world such as Hans Bethe, Richard Feynman, Enrico Fermi and Edward Teller. He became the main coordinator between different laboratories and ensured efficient collaboration and allocation of resources. All the while, the project was veiled in shrouds of secrecy. European scientists migrated to the test site without their families, and communication with the outside world was strictly cut off. It employed approximately 1,30,000 people, mostly American and European scientists and mathematicians. The Project was compartmentalised and only a select few understood its full implications. After Roosevelt’s death in April 1945, vice president Harry Truman admitted to not knowing about the Manhattan Project. The scientists developed 2 designs for the bomb, a simpler gun-type fission weapon, and a more complex implosion-type weapon. The gun-type detonated by shooting one piece of super-critical mass at another. The implosion-type squeezed the fissile core, achieving detonation. After nearly three years of research, the bombs were ready for testing. Oppenheimer nicknamed it the Trinity test. After a successful detonation, President Harry Truman selected Japan as the target for bombing. Japan was the last remaining Axis power and was involved in a brutal conflict with the US. He wanted to end the war swiftly and avoid a costly invasion of mainland Japan. Keeping in mind numerous military and industrial installations, multiple ideal targets were selected in case of poor weather. Targets were also selected to have a demoralising effect on the Japanese army.
On August 6, 1945, America dropped the first nuclear warhead nicknamed little boy with a yield of 15 Kilotons on the city of Hiroshima. It was a gun-type weapon and upon detonation, instantly vaporised 70,000 people. Later estimates put the figure at close to 1,40,000 deaths due to the effects of the bomb. To ensure a swift surrender of the Japanese, the president ordered the bombing of Kakuro. The warhead was nicknamed Fat Man with an explosive yield of 25 Kilotons. Due to poor weather conditions, it was shifted to Nagasaki. On August 9, 1945, the US bombed Japan, killing another 74,000 people. In both cases, an unknown number of people died in the following days due to radiation poisoning and other long-term effects. Despite the tremendous amount of destruction it caused, the weapon was highly ‘inefficient’. Of the 64kg of Uranium in the bomb, <1kg underwent fission. An entire city was levelled from less than a gram of uranium converted into energy.
The entire world was thrown into shock and dismay due to the bombings. Emperor Hirohito broadcasted that his nation would be surrendering to the USA on 15 August. After the Soviet Union declared war on Japan on 8th August, fighting the war was no longer an option. The formal agreement of surrender was signed on 2 September and Japan was occupied by American troops. All military forces were disbanded and demobilized.
The winning side in a war is always death and destruction. Japan’s economy suffered a great deal and multiple cities were reduced to rubble. It did bounce back to become the third richest country in the world, but the scars of war remain. The US remains the only country in the world to ever use nuclear weapons in combat. The widespread destruction and damage caused will forever serve as a reminder to future generations to be wary of the implications of a nuclear war.