My way of thinking leads me to believe that, generally speaking, illegals make a concerted effort to keep their nose clean since involvement in crime is the quickest way back. Residential property management people and tote-the-note car lot salesmen attribute the illegal's prompt pay behavior to the same reason.
I think your off-base in lumping the illegals in with the cross border bandits, who have always been around. You can be sure that the higher the number of illegals crossing, the easier it is for the bandits to hide amongst them.
Perhaps your own last statement might be a good reason to halt all illegal immigration.
BTW, 4Freedom excoriated you pretty good, with your own words. Why come back? I'll bet they're nicer to you at DU.