<i> Will humans stay in the loop? </i>
Going off to war has always meant risking your life, but a wave of robotic weaponry may be changing that centuries-old truth.
The "pilots" who fly US armed drones over Afghanistan, Iraq and Pakistan sit with a joystick thousands of miles (kilometres) away, able to pull the trigger without being exposed to danger.
Other robots under development could soon ferry supplies on dangerous routes and fire at enemy tanks.
The explosion in unmanned vehicles offers the seductive possibility of a country waging war without having to put its own soldiers or civilians in the line of fire.
But analysts say the technology raises a host of ethical and legal questions, while political and military leaders have yet to fully grasp its implications.
"What's the effect on our politics? To be able to carry out operations with less human cost makes great sense. It is a great thing, you save lives," said Peter Singer, author of "Wired for War."
"On the other hand, it may make you more cavalier about the use of force," he told AFP.
Commanders see unmanned vehicles as crucial to gaining the edge in combat and saving soldiers' lives, freeing up troops from what the military calls "dull, dirty and dangerous" tasks.
Cruise missiles and air strikes have already made war a more remote event for the American public.
Now, robots could offer the tantalizing scenario of "pain-free" military action, said Lawrence Korb, a former US assistant secretary of defence.
"That raises the whole larger question -- does it make it too easy to go to war, not just here or anyplace else?" he said.
Robotic technology is taking armies into uncharted territory where tens of thousands of sophisticated robots could eventually be deployed, including unmanned vehicles possibly designed to automatically open fire.