If they could 2/3 of the world’s population would come here. Once they see how people, even “poor” people live in the United States, why would they if rational want to stay in their “homelands”. Either America has distinct enforceable borders, or it does not have a nation.
I guess the “immigrants” have a problem. Coming to the USA is NOT a solution to their “problem”. If they enter illegally, shoot them. There are these things called sovereign countries and there are borders.