I wonder, are there any recent examples where assuming a country had an active nuclear weapons program turned out to be a huge fucking mistake?

Iraq is another reason why you're doomed if you do and doomed if you don't.
What incentive is there for Iran to give up nukes?
A) Give up nukes and watch how the US/Saudi/Israeli alliance moves closer to their borders
B) Keep nukes to prevent an attack and increase their power in the region
People underestimate the fallout of the Balkan wars of the 90's. It showed that the US would ignore international law if they felt it was their duty or they were on the right side of history.
The Russians never got passed that and neither did their allies such as the Syrians and the Iranians.
If Iran didn't have nukes OP Persian Freedom would've launched ages ago. Right around the time they were softening up Syria.
But not even Bibi dares to bomb alleged nuclear sites in Iran in case they actually have nuclear weapons and decide to fire back.
The difference with North Korea is simple. The foreign policy experts do not fear that North Korea would use nukes on their own neighbors. That does not match their policy of reunification.
They fear that the North Koreans would sell their nuclear weapons to other rogue regimes such as Iran and even African states. After all, they've got a substantial illegal trade in chemical weapons already.
All we've seen in recent years is that deals and cease fires like the Protection deal for Ukraine and the UN charter on Iraq are completely useless when one of the big powers (Russia,China, US) wants something.
So let me ask you again. Why would Iran give up their nukes? What reason could they possibly have?