The Hiroshima bombing was one of two atomic attacks on Japan which effectively ended the Second World War and killed about 140,000 to 220,000 inhabitants in the short term.

Author: U.S. Navy Public Affairs Resources Website

How wasn't this a war crime?

It was. But it's OK if the winners do it, apparently.

How did those buildings survive! And what was the temperature inside the buildings?

Earthquake regulations.

It’s a bit like you going to Adghanistan, saying you don’t like Islam and getting beheaded and your body dumped in a river, then saying: this is a human rights violation!

World is a different place when you look up from your books

Massive unnecessary brutality.

Also it's just a flat out lie. They had negociated with the USSR for a ground invasion, which was ready and about to launch.

They only dropped the nukes to try and shock the Japanese and get a surrender without Japan falling to communism.

Which didn't work by the way, the japanese weren't really shocked by the bombings, they had gone through years of civilians getting absolutely massacred by conventional bombings. They surrendered because they had exhausted all their resources, which the nukes had little to do with.