How could you protect your wife if you move to a country with nazis, and your wife is not white?

?

If you know in advance that the government or the people would be biased against a member of your family, your best protection would be not to move there. Beyond that, it would depend on the degree of threat and whether the government offered any protection.

They are so many places where you can live without those problems. Keep seeking because you are going to cause them, by moving there.