If there remains one mining pool that does not adhere to these legislation and can be managed in countries that have a political stance towards the United States, then all the other mining pools will be forced to build on top of that block
No, it doesn't. If censoring mining pools have 51% of the hashrate, then they can permanently exclude any transaction they wish. If a normal mining pool mines a block which includes a "blacklisted" transaction, then the censoring mining pools with a majority of the hashrate can simply ignore that block and re-org it out with 100% certainty.
Well, they can. OFAC compliant pools seem to control the vast majority of the hashrate right now. If they want, they could fork the network and maintain the longest chain even now. But will they?
They're already losing out on fee revenue by excluding otherwise perfectly valid transactions from their blocks just because of OFAC. Hard forking by completely ignoring perfectly valid blocks just because they include transactions by BTC addresses in the OFAC list would likely create a very big debate.
Core developers would have to decide which chain to support, big services would have to announce their recognition to what they see as the main BTC etc. It would be wild to see. Miners stand to lose a lot of revenue.
I think big pools will just chose to filter transactions without forking. This status quo maintains their revenue and they can also claim non-participation in BTC "money laundering".