> If we let the entire world in, our GDP per capita would go down.
Immigration can make everyone better off, even though the GDP/capita declines.
How can this be?
Consider this thought experiment.
Suppose in 2024, you lived alone on a desert island.
And suppose you made $100 K/year.
The GDP per capita would be $100 K/year, right?
Now suppose in 2025,
1. Your income increases to $110 K/year.
2. A Haitian moves to your island.
3. The Haitian immigrant make $40 K/year.
The GDP/capita would be ($110 + $40)/2 = $75 K/year.
Even though the GDP/capita declined, you're both better off, right?