The point you consistently miss is the influence financial capitalism has played in the massive refugee flows you "warn" about today:
America’s Path To A FIRE Economy
European and US investors used their respective colonial systems to drain raw materials, labor, and wealth forcing their colonies to produce commodities like tea, coffee, and minerals that were shipped abroad, causing domestic starvation.
And you blame the starving victims for immigrating instead of the rich parasites who became much richer by instigating the system of extraction over development.