IT SOUNDS like every general's dream: technology that allows a nation to fight a war with little or no loss of life on its side. It is also a peace-seeking citizen's nightmare. Without the politically embarrassing threat of soldiers returning home in flag-wrapped coffins, governments would find it far easier to commit to military action. The consequences for countries on the receiving end - and for world peace - would be immense.

This is not a fantasy scenario. Over the coming years, the world's most powerful military machine, the US Department of Defense, aims to replace a large proportion of its armed vehicles and weaponry with robotised technologies. By 2010, a third of its "deep-strike" aircraft will be unmanned aerial vehicles (UAVs), according to a Congressional Research Service report issued in July (http://tinyurl.com/yafoht). In a further five years a similar proportion of the US army's ground combat vehicles ...