Last week, I heard a talk from one of the engineers doing this. He claimed that the main thing holding back robotics is liability concerns. If someone builds a machine that causes widespread death and destruction, the usual cop-out is to blame the operator for losing control of it. But if a fully autonomous robot goes postal, the manufacturer can't pass the buck to anyone.

Perhaps this will be a real issue, or perhaps robot engineers are a bit too fond of Terminator and 2001. Fear of it is apparently causing real effects. It would be sad if the ultimate reason to employ humans is that it feels good to kick their arses when things go wrong.