The purpose of the nuclear bomb was the same as the purpose of strategic bombing in general - to destroy buildings and infrastructure and kill people indiscrimi

The purpose of the nuclear bomb was the same as the purpose of strategic bombing in general - to destroy buildings and infrastructure and kill people indiscriminately. The nuclear bomb was not fundamentally different in that aspect - strategic bombings had been going on for years and was highly destructive and deadly already. For example the firebombing of Tokyo with conventional bombs killed more people than the Hiroshima nuclear bomb. So the use of nuclear bomb did not require any special explanation or justification. It was natural extension of the strategy in use. Of course it can be said that the purpose of the use of any weapon is to win and thereby end the was sooner, hence saving lives in the long run. In that case the purpose of any bomb, tank, landmine or gun is to save lives.