As Christians, we are to help our own family first.
Then Christians nears us, then Christians far from us, then others.
Non-Christians are last on the list.
Certainly if the need is great and immediate, we should help.
But we are not commanded to help everyone everywhere.
We should not help those who refuse to work.
There is no command to allow alien non-Christians to take over the nation.
This link seems a pretty good summation:
https://www.9marks.org/article/journalhow-should-we-think-about-our-obligation-help-poor/
Secular “liberals” conflate world affairs with heaven affairs.
The problem seems to be that “conservatives” are trying to do that too.
I believe he real answer, if God grants success to it, is a combination of evangelism, foreign missions, and “ordinary” law enforcement. We don’t need any new rules. We just need to quit winking at the old ones.
It’s hard to be utterly wooden about this. The divine answer would be something like “as opportunity and means and genuine desire make possible.” Nobody is helped with the intention that he or she would then always be selfish. Not family in the room, not the evangelized person way off in Timbuktu. It’s set up by the Lord to be a chain reaction of divine blessings, inasmuch as the souls to do it with are placed by the Lord.
There isn’t any “Christian country” in the bible sense. There are a lot of lands with significant Christian presence and influence inside them.
It may be possible to even get a divine blessing of a lot of Christians in a land by praying the Lord that He would destine those souls in. And by being willing to send the evangelists out to meet them. The spiritual equation balances just like a chemical equation might. Behind the scenes, it is by divine plan.