Lean, green killing machines

As the Taliban gunman hides from an approaching Apache attack helicopter, he may not care that the American aircraft is painted with chrome-free primer to reduce its environmental impact. Nor may he be impressed that the next generation of pilotless surveillance drones will be part-powered by solar energy.

The US military is rushing to embrace sustainability. Its primary motive is not ethical. It is trying to keep pace with China in a strategic race to harness clean energy. Any future conflict between superpowers will almost certainly feature eco-weapons and green tactics. The oil-burning Americans are starting to realise how badly they are lagging behind.