Today, one nuclear warhead is over 10 times more powerful than the bomb dropped on Hiroshima and has the ability to kill over a million people. From that point forward, both the USA and USSR entered into a race to stockpile as many nuclear weapons as possible. In fact, some historians this was the eventual downfall of the Soviet Union: they had become bankrupt from a very expensive military expenditure, but the economy did not support it, whilst finances in the west flourished.