.taking the possibility out of the hands of nutters
Maybe this isn't worth repeating - but no one has ever used nuclear weapons other than the United States.
If the problem with Iran and nukes is that they are Muslim - then you have Pakistan which has still not nuked India.
I would argue that the only place right now where nukes are in the hands of nutters is exactly in Israel.
The country most likely to use nukes - Israel. Netanyahu constantly talks about "existential" threats in very messianic tones. That's pretty much the textbook definition of "first strike" doctrine.
The underground complex at Fordow - is likely impossible to disable fully using America's GBU-57 bombs. This would require pinpoint precision, where each bomb falls exactly into the "hole" that the previous bomb made, and the bombs are essentially used as a huge aerially dropped percussion drill. It's extremely cheap, to deploy GPS spoofing systems (on the order of tens of thousands of dollars). There is every reason to think, that the area around the mountain is chock full of electronic counter measures. This means the GBU-57 cannot rely on GPS, and has to rely on its onboard INS. The onboard INS cannot guarantee a CEP better than 10 meters.
This means, there is a very high likelihood that every subsequent bomb is gonna hit slightly off center, and simply expand the crater and toss dirt in different directions without making the hole any deeper.
The only real ways to disable the plant are:
1) A ground operation
2) Sustained and methodical bombing by conventional munitions, for potentially days or weeks. Basically erasing the mountain with explosives.
3) A nuke
So beyond always talking about "existential threats", Israel also has a potentially very practical need to use nukes.