Were you intentionally being ironic? (thinking of certain racist politicians, covert-sponsored terrorism and such of a particular nuclear power-immaterial to the gp's post, but curious nonetheless).
Anyhow, rather sure when Russia and China were developing the bomb a lot of freaking occurred, but as no one was in a position to stop them, nothing came of it. Also, there are also several 'brown' nuclear powers currently existing who behave rather 'immaturely' and are verging on war, but we don't hear talk of taking their nukes away.
The difference here is that Iran does NOT YET have the nukes and so can be stopped from joining 'the club'. If they somehow manage to make it to the field testing stage, (my guess is) interest in intervention will fade rapidly by several powers to the point of just stern lectures...albeit Israel might take a different response. The seem to potentially have the most to fear.
Personally, I don't see this so much a race issue so much as a "let's stop nuclear proliferation, it dilutes our own power, and it is scary in the hands of non-allies'.
- - - -
Wonder why they just don't drop two bombs if they can't reach deep enough. Are the bombs not precision guidable, or is hitting rubble mitigating the penetration capability?