I think the primary use of true WMD scale devices has historically been entirely defensive. Chemical weapons are largely not used due to various reasons including complexity and ineffectiveness. Nuclear weapons weapons were used twice, and caused the two most powerful military systems in history, led by relatively bellicose leadership at times, to go to great lengths to avoid anything that could escalate.
I would credit the lack of WMD use to a) the inflexibility/limitations of non-nuclear WMDs, and b) the good fortune that nuclear weapons were bottlenecked on hard industrial and material inputs. If you expanded the number of people with access to nuclear weapons, I don’t think you would see everyone rationally withold from using them forever. I also think this somewhat mischaracterizes the attitude towards nuclear weapons use during the Cold War. Early on, launch authority was often delegated to commanders in the field, and they were very nearly deployed during the tension around the Cuban Missile Crisis and during the Korean War.
Nuclear weapons are also asymmetrically useful for weak states, because they negate conventional military superiority (see: North Korea). They don’t let you take or hold territory, and so don’t assist conquest. But we still would be incredibly worried to see them proliferate widely, as drone swarms are likely to do. Even if they never got cheap enough to quite make their way into the hands of non-state actors, we would be always running the risk that small regional conflicts explode into extremely lethal wars.
I would credit the lack of WMD use to a) the inflexibility/limitations of non-nuclear WMDs, and b) the good fortune that nuclear weapons were bottlenecked on hard industrial and material inputs. If you expanded the number of people with access to nuclear weapons, I don’t think you would see everyone rationally withold from using them forever. I also think this somewhat mischaracterizes the attitude towards nuclear weapons use during the Cold War. Early on, launch authority was often delegated to commanders in the field, and they were very nearly deployed during the tension around the Cuban Missile Crisis and during the Korean War.
Nuclear weapons are also asymmetrically useful for weak states, because they negate conventional military superiority (see: North Korea). They don’t let you take or hold territory, and so don’t assist conquest. But we still would be incredibly worried to see them proliferate widely, as drone swarms are likely to do. Even if they never got cheap enough to quite make their way into the hands of non-state actors, we would be always running the risk that small regional conflicts explode into extremely lethal wars.