This opinion is unpopular with a lot of people I've talked to, but I don't care. There are over 320 million people living in the United States and the rate of growth is exponential. There is not enough jobs, money or resources to go around especially when automation is ramping up and killing the need for humans. Truck Drivers, Teachers, Retail, Restaurants / Fast food, warehouses, farming, some IT jobs (especially because of cloud services), and I can go on all day. I hate saying this opinion especially because I know a lot of people seek to be here in the United States, but this can't sustain for very long. Also, this should apply to the world, but since I live in the United States, I can only focus on our country.
I might be wrong and someone can point it out. Most of this is just me speaking from the top of my head.