There's some other reasoning here too that one of you touched on that didn't elaborate on: motivations and ideology for nuclear or potentially nuclear state. Religious fundamentalists would have a much lower threshold than other states with it since they'd be martyrs in heaven if they ended up dying themselves in relatiation after having launched nuclear weapons to kill their enemies. South Korea didn't act like Israel when North Korea gained/ were clearly giving signs that they were gaining nuclear weapons because of the nuclear umbrella and the fact that (at least given the nuclear umbrella, if the US would rescind that for South Korea, well, different story) it was just deterrence and insurance of an isolated regime. And as for Russia, well, for the most part their leaders haven't had an urge to press the button to end their enemies in a first strike since it'd end them too. Iran could be a different story, and it's not just the actual state mechanisms itself that could be a danger, but other radical groups within it that might have an easier time getting their hands on them that Iran themselves might not have that much of an easy time controlling.
If you look at historical documents, the Soviet Union never wanted to use Nuclear weapons offensively. In fact they thought we were going to bomb them first due to all hands on deck pressure. That's when the Stanislav Petrov situation happened. The same happened in a nuclear submarine by Vasily Arkhipov.
The only danger in my mind with nuclear weapons is that a country will dissolve, the United States will dissolve, Russia will dissolve, France/Germany/South Korea, all it is time and strain on the system for it to collapse. When that happens the weapons are free in the wild which is bad.
Iran isn't due to have a Nuke in 2025 (keep in mind most of the big money on polymarket are insiders and there is heavy correlation with those in polymarket betting high money, and being correct, thus being connected enough to make educated bets).
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The American suspected bombing campaign against Iran has not affected it heavily, and they aren't even expected to have 90% before june.
Will Iran enrich uranium to 90% before June? (Resolved): View final results and past odds on The World’s Largest Prediction Market™
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I agree it'll be a unpredictable government with a nuclear weapon, but North Korea was hyped up as insane and unstable and they are doing fine with their current nuclear weapons (hyped up as crazy by American Intelligence). Now, we are doing the same to Iran when it's well known both Iran and NK fund terrorist groups and hacking groups. Israel is also considered a more radicalized country in terms of religion base. They haven't done anything with theirs either when many countries said they'd do something bad and crazy with them.
When you risk your entire ideology dying to a nuclear response/attack you won't risk it. Nuclear weapons are defensive and used when your ideology is in threat of extinction via outside sources. Natural internal sources don't justify it.
Else USSR would have self detonated.
Israel nor North Korea are facing extinction which is why they haven't had to use them offensively. the USSR/RU never faced extinction via an outside source which means their ideology wasn't going to go extinct via an outside force. WW2 the threat of extinction for many ideologies were on the map and America used it offensively, and were willing to use it against Germany.
Look at American historical production, Recruitment, and other key metrics at the time and you'll understand why they used the Nuke. In addition they had a strict timeframe to use the nuke because it was known Germany was creating one themselves so America wanted to end the war quicker because if Germany had the time to make it, it'd become a stalemate because they could then defend themselves and their ideology with the nuke. (or possibly) use it to swing themselves back into the war till America produced one, then they lock each other into a stalemate of willing to destroy to preserve idology from outside military influence.
KEY: The only reason why Germany didn't beat America with getting a nuclear weapon was because of British SAS bombing the facilities. That is the single biggest point during the whole war that secured allied victory along with the dropping of the bombs on Japan. But you aren't going to see much of that advertised in the history books because it's not good for american superiority ideology.
Nuclear weapons protect ideologies from outside pressures. Not internal pressures.