How are Africans who live in tin roof sheds with dirt floors able to pay for the passage, as well as the fees of the human smugglers?
Just a guess:
https://www.opensocietyfoundations.org
Many of our past immigrants were very poor.
But they were ambitious and educated or willing and able to be educated.
They looked at the USA as the land of opportunity, not the land of the handout.
A lot of this poor immigrant bunch have the wrong attitudes, little education or willingness or ability to be educated.
We need productive immigrants to keep the social security Ponzi scheme going.