[friend_and_foe]

This has never happened in history. If the land your people are on has resources and is accessible, you'll get subsumed and assimilated by another one, one way or another. If you want your nation to survive, you have to 1) have a healthy rate of admixture fast enough to prevent inbreeding but slow enough to protect the culture, 2) get to fuckin'. The latter may require some reorganizing of the labor and housing market to make raising more than one or two kids feasible. But if you think your people can fizzle out, you're going to be disappointed whether you like it or not. And it doesn't matter what the government does, they can try to stop it, at some point there's just not enough able bodied of you to utilize and protect your resources. Building a wall around fertile land and staving off migrants who want it til the last one of you dies out is just not going to happen.

[no_time]

It's working well enough for Israel. Technology and disregarding international treaties goes a long way.

[seanmcdirmid]

War and genocide are options, even if they are horrible ones that shouldn’t be considered. Throughout history, however, cultures assimilating others have often been violent (either through great defense or great offense). European assimilation of the Americas was extremely violent and destructive.

[friend_and_foe]

Yes, this process almost always is accompanied by fierce conflict.