So, a couple of variables you are missing with your generous comment. Allow me to explain. You have described pretty much everyone on south, central, and north America. They all want to come to United States because the people in United States did the right thing at one point that allowed for its people to grow and prosper. Letting people in, good amout of them are uneducated, some are criminals, murderers, abusive. We do not know, so you just can't let everyone in, you have to protect your people against those. Now, countries in south, central, and north America have resources just like United States, so why are they coming here? The solution, just as seen in South Park Time Immigrats episode, is to go to those countries and help them there, overthrow their corrupted politicians SO THAT people in those countries can enjoy their own country's riches, live a dignified life AND not have to illegally cross a border. Doing something illegal still a crime. It is not fare for those who worked hard to come to United States legally either, think about that. So no, we can't let them in, it does not help anyone. You want to help them, you get off your confort zone and go help them at their country.