You really should. They are corrupted, racist and dirty as heck. So bad that there's a good chance they could go socialist/communist in the near future. To have a government like that right next to us could be a major concern.
And an unintended consequence of completely shutting off the flow of workers from there to here might well be to start the requisite revolution.
As it stands now, we're a safety valve for those Mexicans who happen to have the gumption to do something to better their conditions. You can be sure that Vincente Fox knows that....
There's a lot more to this debate than the "build a wall" types are willing to admit.
They've been socialist/communist since the 1920's. Why do you think so many Mexicans are coming to the US?