I remember TFM on the Killstream arguing that they HAVE to do this because the welfare state would collapse with the current birthrates (either that or bite the bullet and perform massive cuts). In that view the Western world is being set up as a nursing home for the aging white race, and they don't like rowdy or ungrateful residents.
I doubt its some decades to centuries long vendetta against whitey by (((them))) (or insert your favored conspirator here) that came to fruition. It's probably an accumulation of band-aid fixes to the side-effects of things that seemed like a good idea at the time. Unless they truly wish to become third world slum lords in gated communities with heavily armed guards.
As much as I like to roleplay against the Zionist menace, none of this shit is new.
Back in the 90s, the societal replacement in western Europe was poles and slavs - I mean, slavs aren't white, but you get the picture. In the US in the early 1900s it was Italians and Irish.
Melanin content is immaterial, what you want is a cheap labor force you can control.
There is a fair bit of trying to keep the wheels on the welfare state, but that is all secondary to ensuring your & your cronies are the elites.
And again, they already live in gate communities. They only difference is the walls will get higher and there will be more guards; but they won't notice.
Venezuela is melting down - people are starving, hospitals are out of medicine, the country has rolling nation-wide blackouts, the currency is worth less than paper its printed on to the point some shops have gone back to barter systems, and there is widespread kidnapping and gang violence.
In Brazil, the middle class neighborhoods all have bars on the windows. The poor live in crumbling tenaments where the police don't go unless they are conducting Iraq-type locked-and-loaded roll outs. Kidnap for ransom is wide spread with the police usually in on it. The people at the top were also siphoning billions to line their own pockets. And the less said about what they're doing to the Amazon the better.
The folks at the top don't have any of those issues. They've got fat bank accounts and send their children to college in Europe. None of these issues affect their elites directly. They live in safe, walled enclaves protected by men armed with the weapons they work to deny their citizens.
In the US, it would be a fairly easy matter to start leveling criminal charges against anyone who is found bypassing E-verify during hiring. Once people can't get jobs without proper papers, illegal immigration stops being an issue.
This never goes anywhere because too many businesses make too much money by hiring people without work authorization, because you can hire them for less, treat them worse, and if they are too big of an issue you turn them into ICE.