It wasn't until the cost of fuel was measured in blood that the commanders started to understand

“Our transports have never been as vulnerable and exposed as they are in Iraq. More oil is not the solution, it is the problem,” Dan Nolan, who oversees energy projects for the US Army's Rapid Equipping Force.  As a consequence the Army now tries to generate what is needed on site; they use fuel cells which produce water as a byproduct. They use tents that need 40 percent less air-conditioning, which in turn is now increasingly run on green energy instead of diesel. The diesel generators emit heat, which is easily spotted with infrared detection.