a lot of them come here to gain education, skills and a network of support, then go back to their home countries better equipped to help improve them.
how to help lift your countrymen up if you make $10 a month in Central America? but if you can make $1000 a month by emigrating to America that you can send back home to your family . .
this is one of the main reasons that we have so many people trying to cross the southern border. i'm not sure that bankrupting Mexico by forcing them at gunpoint to build an enormous wall is the best way to treat the problem. i think that if we could somehow help Central American countries root out their own corruption and grow their own economies, so that there was the same kind of opportunity in people's homelands as there is here, it would do a lot more to stem the tide than just beefing up security will ever do.
to me, it's like treating the symptoms vs. the cause. i don't know that anyone running for office looks at it that way or has those kinds of proposals though (?) -- Trump certainly doesn't.