Sweden is also ten million people. Just a touch larger than the San Francisco Bay Area. It's also not all that diverse, a quick google search says 80% white, and those ten million folks are just short of a trillion dollars in debt. They're living high on the hog now, but shit's going to get serious when the bills come due.Sweden has a higher standard of living than the US and doesn't have massive oil reserves so clearly that is not necessary. Several other European countries also achieve this without significant mineral wealth.