Today, in 2011, one out of every fifty soldiers in Afghanistan has battery acid and lubricant instead of blood, sweat and tears. This means that, based on total army enlistment, "robot" is roughly as large a demographic as "asian". At least among the troops stationed in that theater.
It's worth noting that most of these droids are very simple, in terms of their higher-functioning capabilities. They work to disable (or set off) explosive devices and inspect vehicles and blaze trails and other dangerous tasks that are best handled by something that doesn't mind bullets. As it stands, our "AI" programming is too limited to allow any of these robots very much autonomy.
There are plenty of armed robots "over there", though, and there is a great deal of debate over how they should be used. The Conflict Monitoring Centre reported that the last five years saw as many as 2043 people killed in US drone attacks in North-East Pakistan. The majority were civilians- although identification either way is made difficult by the fact that robots can't tell the difference between civilian farmers with rifles and dangerous bandits with rifles.
So yeah...maybe those unmanned stealth bombers aren't the best idea ever.