The more countries with nuclear weapons, and the more unstable or extremist they are, the greater the likelihood of an eventual detonation, even if accidental. 40 years ago, everyone understood this and agreed nuclear proliferation was bad, the US and USSR committed to reducing their stockpiles, and Reagan himself expressed a desire for complete nuclear disarmament, in part because of the near-catastrophe of the Abel Archer incident--a catastrophe only narrowly avoided despite the US and USSR both being stable superpowers led by rational actors. Anyone encouraging nuclear proliferation for every tin-pot dictatorship or gay-lynching theocracy to make the world safer is insane.
> effectively uninvadable
Yet Israel was invaded during the Yom Kippur War when it had nuclear weapons, the UK was invaded by Argentina during the Falklands War, Russia was invaded briefly by Ukraine (Kursk). And Israel arguably just demonstrated that developing a survivable nuclear deterrent probably isn't as easy as many thought. (Ukraine, to a lesser extent, also with Spiderweb.)
> Supporting Israel in preventing Iran from getting nuclear capabilities is destablizing, not the opposite.
On the contrary, it sends a strong "fuck around and find out" message to any country pursuing nuclear weapons. And if Israel is capable of this kind of decapitating strike against a country's nuclear program, imagine what the US (or China) could pull off.