Another thought experiment

Suppose that the Democrats created a platform which aimed at creating a peaceful multicultural USA and finally resolving the central American problem of (White) racism by envisioning a population as follows:

25% Black, 35% Hispanic, 10% Asian, 5% Other and 25% White.

This would be achieved non-violently over a few decades, by a variety of immigration measures and legal and financial inducements.

On what grounds could American Whites, either Liberals or Conservatives, oppose this?

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