And a single nuke on Israel would prompt the same response.
So Iran kills 1000’s in Israel..then what? They have nothing left and are promptly decimated.
A single nuke is not an arsenal. It's just one BIG bomb. One shot. If anyhting with would be used to cause massive upheaval in the ME while at the same time resulting in unprecedented action against Iran.
I think even Russia and China would raise some eyebrows if Iran actually used a nuke.
A single nuke is not ONE big bomb. It is the ONE big bomb which assures you will be left alone to produce MANY big bombs and, eventually, the means to deliver them.