Robo-warfare is making it too easy to wage arbitrary war, and is by historical standards cowardly, usually entailing overkill to achieve a limited target (like swatting mosquitos with hand grenades. Can you say "collateral damage"?). To bring no risk to warfare is to undermine the principle of Just War, where people voluntarily enter into war upon principles of justice (self defense), and risk their own lives bravely and willingly. Sending robots risks nothing, and makes unjust war a no-risk situation, and therefore too easy to begin. Also there is the danger factor where human judgment may be lacking instead of a programmed response, without the ability to correct or withdraw destructive actions.

Ask the civilians in Afghanistan or Pakistan what they think of drone (Predator) UAV bombing flights so far. More civilians have been killed than 'terrorists".

See this article too, albeit not up-to-date with the most recent stats:

Of the 60 cross-border predator strikes carried out by the Afghanistan-based American drones in Pakistan between January 14, 2006 and April 8, 2009, only 10 were able to hit their actual targets, killing 14 wanted al-Qaeda leaders, besides perishing 687 innocent Pakistani civilians. The success percentage of the US predator strikes thus comes to not more than six per cent.

With "kill stats" like this, how is the use of UAV's for "hunting terrorists" justified! How safe the U.S. military is, hiding behind Joysticks to do this, as if killing people is a game.

Video of new Reaper UAV in Afghanistan here.