No need to be killing folks. Though I admit I used to think that way too, Fitz... landmines, border patrol with helicopters with door gunners, etc. I even volunteered with the Minutemen back in the early 2000's.
It's an easy fix.
See those giant squarish backpacks they're carrying? That's a marijuana train. They pay their way to come here by muling pot. I've seen those same trains myself.
#1 - Legalize pot. When the high school kids can grow it in the family garden and the worst they have to deal with is mom and dad rolling their eyes in dismay, all the violence and drug trafficking over the stuff disappears.
#2 - Get rid of the welfare programs. It's not the full incentive they come here for, but it's part of it. Maybe 25%.
#3 - Get rid of the free pass at the ER. If you're an illegal and show up at the ER and can't pay for your medical care, you go to jail. Long enough to screw up your income stream back home (90 days would do it), then deported.
Frankly, those three things would turn us from being a 15 million illegal alien country, to a 5 million illegal alien country.