It may disregard its massive carbon emissions and try to explain away the greenhouse effect. But when it comes to defence equipment, the us is choosing to play it environmentally safe.

The Pentagon is paying Minnesota-based Alliant, the world's largest ammunition manufacturer, us $5 million to develop lead-free combat bullets. These bullets would, of course, be lethal for their targets, but safe for the environment. "(With lead bullets) there is a cost in terms of health, human safety and cleanup