The mystical, elusive White Elysium. The nαzιs tried & completely failed. Apartheid South Africa failed. There is a trend here.
Galatians 3:28 - There is neither Jew nor Greek; there is neither servant nor free; there is neither male nor female. For you are all one in Christ Jesus.
The Catholic State is the best option. Natural birth rates would correct any fears of a white decline without any racist policies. In Germany, traditionally Catholic rural areas actually had issues with a lack of inheritors/farmers due to vocation booms causing surplus lands. In Protestant Germany there was land scarcity amongst farmers because all 8 kids all wanted a share having families of their own, causing a drift to city-poverty. A German Catholic family could have 8 kids, and the majority could take a vocations leaving land and forest areas unused. So there weren't issues with land scarcity - the opposite actually due to children deciding to become celibate religious.
Pro-natal policies actually make sense with Catholic values. Otherwise, unsustainable growth and competition for resources leads to instability.
Traditional Catholicism is most in tune with nature. White Nationalism is pagan and egocentric and generally collapses according to historical trends. Protestantism with its forced marriages leads to instability, land grabs and expansionism.