Predator Drones vs. Water Boarding

There is an interesting talking point brought up in hawkish counter-terror circles right now regarding water-boarding. The question boils down to:

How is more justified, legally or morally, to kill a terrorist via predator drone than to water-board a terrorist for information about future plots?

They argue, killing a terrorist via drones is essentially summary execution of the individual. How can that be considered morally and legally justified while water-boarding (which we actually subject our own armed services people to as a form of training) ought to be considered morally and legally unjustified?

Who is being loose here with distinctions? Those who consider water-boarding torture and all torture wrong? Or those who consider water-boarding enhanced interrogation? Who is being euphemistic?