But the Border Patrol's new use of unmanned drone surveillance planes has displeased immigration advocates and others.

The remotely piloted Hermes 450 craft, which can stay aloft for 20 hours at a time, are not armed with missiles like the Predators that gained renown in U.S. military and CIA operations. Predator-fired missiles have killed several top al-Qaida operatives in Afghanistan and Yemen.

The Border Patrol drones will carry cameras with thermal and night vision capabilities that can detect movement 15 miles away as they fly over vast stretches of cactus, mesquite and scrub-covered deserts, mountains and sprawling grasslands.

Still, it won't matter if we can watch tragedy unfold, yet affect it not, if there is insufficient manpower to send a patrol to the destination marked by the drone. And what if weapons are added to these drones as part of future program enhancements?