The most glaring example of this phenomenon, so obvious you could miss it, is the US of A.
Have you ever considered the logic, if any, behind opening the floodgates to unskilled, illiterate Central and Southwest Asians (a/k/a Eastern & Southern Europeans) in the late 19th and early 20th centuries? I mean, there were enough Blacks in the South, Native Americans everywhere, and East Asians in the West to do any needed work, who were already citizens, and knew the language, right?
The issue was quality, not quantity. Black men and women, teeming masses of skilled, energetic people who had just fought and won their freedom in the biggest slave revolt you’ve never heard of, a/k/a the Civil War, were poised to take over.
The problem of open competition with “blacks” had been anticipated. Abraham Lincoln, the racist White Savior, after ‘freeing’ Africans from states that weren’t even under his jurisdiction, had proposed to ship them to Central America.
“It is still in our power to direct the process of emancipation, and deportation, peaceably, and in such slow degrees, as that the evil will wear off insensibly; and in their places be, pari passu [on an equal basis], filled up by free white laborers.”
“As long as blacks continue to live with the whites they constitute a threat to the national life. Family life may also collapse and the increase of mixed breed bastards may some day challenge the supremacy of the white man.”
This is the fear of many “white” people until today, in fact, and the difference then was that it was something they would openly talk about.
Mass deportation didn’t happen, and America was too war weary to wipe them out like the Native Americans, so they had to dilute the population by replacing the millions of “white” men who died in the war with “‘white’-enough” immigrants, including Roman Catholic Irish, for whom the first English word they would ever know would be “nigger.”
4. South Africa