Guilt. Europe is dominated by sneering liberals who basically hate their own country. If you said to the average Japanese person “would you like a few million African migrants over the next decade?” they would reply “of course not! That would totally change our racial and cultural identity. We are fine the way we are. Why would do such a crazy thing?” To the Japanese (or Chinese) it seems perfectly natural to want to preserve your identity. In Western countries, multiculturalism and racial diversity have become new religions. People are hysterical about both and won’t tolerate any criticisms or objections. In general, it is the liberal middle-classes (hidden away in the leafy suburbs) who defend multiculturalism and mass immigration, and it is the white working-class (those who have to deal with the consequences) who oppose it.