200k people were vaporized by atomic bombs in an utterly indiscriminate manner. This is inclusive of babies, little infants literally melted in a second. The radiation persisted decades after the blast.

We give it a special status despite conventional warfare still being capable of greater numbers, because of how exceedingly cruel and indiscriminate it is.

Historians described it as an 'ethical shock' and I agree with the term. If the yanks did not elect to exclusively melt civilians with their demonstration history might look at it differently.