> Acts like firebombing of Tokyo or bombing of Dresden or atomic bombing don't happen now

We still raze cities and drop incendiaries. America hasn’t gone to war with a near-peer nonnuclear power like Japan since WWII. To the extent we were faced with the prospect in the Cold War, both we and the Soviets were committed to MAD, i.e. using nukes. (Do you think unilateral disarmament in the Cold War would have lead to peace?)

There has been no militarily useful technology that was voluntarily abandoned. Just constrained. You can’t constrain a technology you don’t bother understanding.