Thank you for the knowledge. I wasn’t aware this concept existed, but it explains a lot.

It works the same way with demographics as well.

Colonize a place and eventually you make allowances and permit some sort of "very strict" immigration from the colonized places. "The Goods Ones" and a few politicians that carrier water for you. But once you've broken the seal, it's a slippery slope. Not too long after that you have "natives" who have squandered or never even had generational wealth that was the proceeds of colonialism seeing how they've been matched or out-classes by another group, and start to feel loss aversion.

Also works with foreign wars, as they require collaboration with a side in that war. Suddenly you have translators and local staff and spies and politicians and sudden spouses of soldiers, all legitimately asking for a taste of what they and their family suffered for (often quite a bit more than the foreign fighters, who sat in a tent directing things).