From 13 to 15 February 1945, British (and some American) heavy bombers dropped 2,400 tons of high explosives and 1,500 tons of incendiary bombs onto the ancient cathedral city of Dresden. In just a few hours, around 25,000 to 35,000 civilians were blown up or incinerated.
Chief of the Air Staff Charles Portal had calculated that bombing civilians could kill 900,000 in 18 months, seriously injure a million more, destroy six million homes, and “de-house” 25 million, creating a humanitarian crisis that, he believed, would speed up the war.
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