Because it was the right time for it:
The first Nuclear weapon was created by a team of American Scientist's, known as the Manhattan project. It was first tested and used in 1945, not long before we used them on Japan.
1964
The first nuclear weapon was used on Hiroshima , Japan . The first nuclear bomb test was conducted in Alamogordo, New Mexico, on July 16, 1945 .
1964
canada
the first nuclear weapon was issued in WW2 created by the americans in a chicargo squash court
The first Nuclear Weapon.
The meaning of the word nuclear weapon, is a weapon that has a nuclear warhead on it.
It is the most destructive weapon ever created.
This nuclear weapon is called an atomic bomb or a nuclear bomb
Nuclear weapon detonations
If by "bomb" you mean a conventional explosive weapon, then the nuclear weapon is more powerful.
nuclear chemicals such as plutonium
NO
no
No. LLNL even tested several Uranium-Hydride bombs in the 1950s. Even though their computer models said the devices should explode, none gave a nuclear yield. One could use the waste from the reactor as a Radiological Weapon, but the reactor itself is not useful as a weapon.
plutonium + weapon