The Nile valley was very fertile and a great place to live for thousands of years...as long as it was asked to support tens of thousands instead of tens of millions.
Besides, where do you want them to move? To our country?
Bingo. Too large a population for the available resources of the region.
Same story in other places on the globe.
Dude, it's a comedy routine from the late Sam Kinison.
Funny thing about nature: If you don’t have enough to eat, you can’t breed...SO you don’t increase the population...stopping the cycle of having people live in places that don’t support life.