There is a direct link between the activities of US and Canadian resource extraction companies in Central and the wave of illegal immigration from that region. Most Americans do not make the connection, primarily out of ignorance. If you destroy towns and villages by poisoning their local water resources, you give the people in those communities few options other than to emigrate to the United States or move to the big cities in their countries.
You think the water crisis in Flint, Michigan is something? It’s nothing compared to what’s going on throughout Central America. Nothing.
The move to the cities, however, is extremely problematic for people who are used to country life. They become subject to being preyed upon by gangs, drug cartels, prostitution and human trafficking rings, etc. If they’re lucky, they are simply ignored and left to beg on the streets and scrounge for good at the local trash dumps.
The better move is to simply start walking north to the US, hopefully hitching a ride on the train known as the “Beast.” Lots of bad things can happen during the trip through Mexico, but once you make it to the US there’s a good chance you can make it across the border and “disappear” in the vastness of the country. So you may get caught and deported. Big deal. You have no hope anyways. You just chalk it up to part of cost of surviving another day.