If you believe otherwise, please tell us which skin colors are incompatable with Western ideals?
You're changing the terms of the debate. The question is not whether non-Western societies can "succeed," whatever that means, but whether Western civilization will survive.
Ideals don't create a civilization; people do. If Western people are overwhelmed by other peoples, the civilization that results will simply not be Western because because the people who run it won't be Westerners. It's that simple. The successor civilization might be economically prosperous, like Japan, but Western it will not be.