Clearly you are applying a different standard to whites than other groups. It stems from your false equation of culture with race. People come from all over the world to participate in the culture and way of life which we have created and in Europe. But any attempt to defend what we have created is in your mind racism. But, attacks on whites and white culture and people is in your mind, not racism.
Even when others want to reduce the numbers and percentage of whites, you cannot see that as racism. But if anyone complained of the number of blacks or Asians, etc, that would be racism in your mind. Clearly a different standard.
Most importantly, American and European culture contains certain qualities which critically need to be preserved. The ability to innovate, for instance has been critical to our economy and way of life, but it is not found in all cultures. Your rules do not allow us to discuss other cultures but if you will think about it you should be able to see that this aspect of culture explains why most of the areas of the world have been stagnant while ours has progressed. Critically when you suppress "whiteness" in favor of other cultures, you cannot expect the innovation to continue. It is not a function of the real estate, but of the culture.
Other cultures have failed to engender human freedoms and especially economic freedom, which is another aspect of our culture central to the way of life which attracts others. I think we are losing freedom as a trade for mandated equality. Other cultures and people are more willing to accept authoritarian government and that can be seen in all the countries which have tried and failed to maintain democracy. Historically, Americans were not willing to trade freedom for equality, but that is changing.