In terms of Europe where nations such a France, U.K. and Germany have huge unassimilated minorities the fact that the Muslim minority has a birth rate of 4.5 children per couple while the indigenous Europeans are below the sustainable threshold of 1.85 live births (or 2.1 by some calculation). Over time that means the percentage of the population that is not assimilated increases dramatically, while the percentage of native Europeans declines. In the U.S. where assimilation is far better this disparity still has consequences. It plays out as Caucasians become a smaller and smaller portion of the total population.
Phi Beta Iota: There was an effort to have a national demographic policy (as well as national industrial and infrastructure policies) but these were quickly dismissed by corrupt politicians working for corrupt banks and the mega-industrial complexes. Ethical evidence-based decision-support — and decisions in the public (99%) interest — are the anti-thesis of decisions made by politicians for a 5% kick-back and in favor of the 1%.