large-scale migration is the future for the next century
It's an unsustainable model. It requires some countries to remain social basket cases so that the excess population can be transported like sacks of potatoes to new, better run countries.
But if recent history is any guide.... most of the new arrivals never really adapt and end up long term welfare pets (or wards of the state if that sounds nicer). Worse yet, they actively undermine and sabotage the process of their children adapting and being assimilated to the new country so that the welfare dependency becomes generational.
The better run countries simply cannot remain better run if they keep up the mass importation of culturally incompatible people. I would think this is blindingly obvious over the last 30, 20, 10, 5 years but those in decision making positions remain as willfully blind as ever.