The challenge for Israel is there's always a small chance your intelligence has a blind spot or is wrong. You can't prove a negative.
This is why I think the most likely scenario is that Israel will commit to regime change. Israel can't trust the current regime to not race to a nuclear weapon at this stage, and Israel can never be over 99% certain that a clandestine effort isn't being done outside of the current understanding of intelligence. "Assume the worst" seems to be a doctrine they adhere to.
And honestly I'm ok with Israel attempting to force regime change. I think they'll fail but whatevs.
The problem is that the US government appear to support them in whatever craziness they aim for. That's the part that makes this a lot more problematic.
There was regime change against the Russian Tsar in response to his failures in WW1. The rally around the flag didn't count for anything. If the weakness and failures of Khamenei becomes a reality strong enough to pierce through the perceptions shaped by state run media then I am putting my money on regime change. Maybe not right now but soon.
Happened with Japan in WW2, too, although that was a surrender rather than bottom up. But still a form of regime change. There are many ways it could play out.
This is why I think the most likely scenario is that Israel will commit to regime change. Israel can't trust the current regime to not race to a nuclear weapon at this stage, and Israel can never be over 99% certain that a clandestine effort isn't being done outside of the current understanding of intelligence. "Assume the worst" seems to be a doctrine they adhere to.