The transformation of nations by immigration, and especially illegal immigration, into multicultural and multiracial societies, destabilizes the nation state system, inviting world war.

When each nation is comprised of a single race and a single culture ("way of life"), there are strong forces, wired into every individual, binding those individuals into a cohesive "village" and to a way of life that promotes that "village's" genes and memes. In such a situation, the competition between nations is indistinguishable from the ancient competition between villages in jungles, except for scale. But, lacking the cohesion and common interest that is created by common genes and memes, today's multiracial and multicultural nations are nothing but large jungles. Individuals in such nations have a weak incentive to cooperate to preserve the nation, but such a "weak force" would be swept away by the much stronger forces of race and religion (way of life, memes) if that nation's cohesion was ever put to the test. This also is very dangerous as it weakens such nation states, thereby inviting world war.