> Iran can absorb more pain than the US, but even that has a deadline.
It doesn't. This is the western mentality, thinking you are dealing with sane people.
I'm from Iran (now living in the West), there's a famous Shia motto: "Every day is Ashura, every land is Karbala".
Around 30% of the population are die hard IRGC supporters, another 10% are neutral and the rest don't like the regime.
The problem is that, the war has caused a major rally around the flag effect.
The IRGC has more support than ever now. It's a battle for the Iran now against United States, attempting to destroy people's homes.
I'm not a fan of IRGC. My 20 year old cousin was captured and tortured in Evin prison for 6 months during the Mahsa uprising in 2022 [3]. You can't imagine how much I hate them, but I love Iran more. If I was there, I would be fighting the Americans right now.
Iranians are not going give up, right now, you will have to kill all 90M of us to "win".
[0] https://en.wikipedia.org/wiki/Ashura
[1] https://en.wikipedia.org/wiki/Karbala
[3] https://en.wikipedia.org/wiki/Mahsa_Amini_protests