oh buddy, you may be in for a surprise there, unless you have some viable evidence to back that statement up.

anyway, op's question; they probably could, but, it'll be probably over 10 years before we'll even think about that truly happening -just my opinion.

edit; 'If mankind was dumb enough to make a computer able to get hostile towards humanity's existance; the computer would be too smart and calculating to realize that most of us would be too stupid to be killed by it.'

what if someone decided it was a good idea to use robots to fight their wars, you know, like using robots to kill humans, since robots could be programmed to drive tanks and other vehicles.
also the last part of the sentence makes no sense at all, care to explain?