The first atomic bomb was created during a secret military research called “The Manhattan Project”, in the USA. During World War II, Albert Einstein, together with other European physicists, had imagined the possibility of the bomb and feared that Hitler’s Nazi Germany would invent it first. Together, they wrote a letter to the US president (back then it was Franklin Delano Roosevelt) and suggested that America tried to develop this war-ending weapon before its enemies. Despite this, Einstein, as a pacifist, was horrified by the potential power of the bomb, and never took part in the actual project (and even said he regretted ever signing that letter) – he only thought that Hitler developing it would be even worse.
The head of the Manhattan Project was Robert Oppenheimer, and among the project there were lots of other famous scientists like Niels Bohr and Enrico Fermi. On the other side of the ocean, Werner Heisenberg (another very famous physicist) was working on Hitler’s project to build the bomb, that was indeed under way! Luckily, they never managed to succeed. It is not clear whether Heisenberg was really putting all his effort into building this bomb; someone says that he deliberately delayed it, or even sabotaged the project from the inside in order to help stopping Hitler. Someone says instead that he really wanted to help Germany win the war and never succeeded. He died forty years ago, so we’ll maybe never know the truth!
Anyway, the rest is history, as they say. The first atomic bomb was tested in Alamogordo, in New Mexico. The only two atomic bombs ever used in war were launched on two Japanese towns, Hiroshima and Nagasaki, and caused mostly civilian deaths. Back then, the effects of radiations were not known; not only the victims of the bomb who survived the explosion were affected by them, but even most of the staff of the Manhattan project had worked carelessly and got ill or died because of radiation or plutonium poisoning. This is perhaps the most striking (and dramatic) example of how science can make a tremendous difference, but also of how it can be misused to bring misery instead of prosperity.