Business Insider 

It started with a simple directive: bring down the casualty numbers.

At the time, Former Lt. Gen. Richard C. Zilmer was the commanding general of the most restive province of Iraq in 2006—al Anbar. And at the time, there was primarily one reason for the dramatic spike in American casualties: Fuel.

It was in the months preceding "The Anbar Awakening," the grass roots movement that turned the tide of war in Iraq, and the Al Qaeda insurgency was fighting like a cornered animal to keep a grip on the region. As a result, Improvised Explosive Device casualties had skyrocketed.