For every illegal alien apprehended we simply give them a job... take them down to the border and hand them cinder blocks and cement and tools, everything they need so that they can help build a really nice wall. Pay 'em too. Why, when they're done, they'll be well off enough (and buffed to boot) to go home, live well, buy weapons, and dump their crooked government.
As for all the Salvadoreans and Guatemalans etc, just give 'em the weapons and ship them home, er, maybe do that in reverse order. Hmmm... I think that plan needs a little work.