This is retarded.

1. Millions of people can still be helped
2. USA has little agency to help the other 5bn
3. The millions that do immigrate send remittances so the impact is greatly multiplied
4. The millions that do immigrate have a positive economic impact (granted, not for everyone)

Agree US immigration policy is not the total solution to world poverty, but no one is arguing that it is. Clearly a small, but helpful element.