American army and marine commanders are desperate to reduce fuel consumption. They point out that during World War II, the first war in which American forces were mechanized, each soldier required 4-5 liters (one gallon) of fuel per day. But by 2003, and the invasion of Iraq, fuel consumption was twenty times higher. By 2003, it was accepted that that turning a modern mechanized division loose meant supplying those troops at the rate of 80-120 liters (20-30 gallons) of fuel per man per day. As the 3rd Infantry Division moved from Kuwait to Baghdad in 2003, some 20,000 troops were involved. That required some 200 tanker loads of fuel per day. Initially, the vehicles in the division carry enough fuel to go 200-300 kilometers on internal fuel. But you don't want your vehicles to run until their tanks are dry, so at least once a day, you try to top everyone off. The route of the 3rd Infantry Division covered about 700 kilometers of road. In addition to fuel, you need about a 45-90 kg (100-200 pounds) of other supplies per man per day (mostly ammo, but also batteries, food and the like.) Once inside Baghdad, and no longer moving all the time, the fuel requirement came way down. But on the march, the advancing combat brigades were tethered by convoys of fuel trucks going back and forth to the supply bases in Kuwait. But once the U.S. began building bases for the combat brigades, it was found that the use of generators, especially for air conditioning, kept fuel requirements high (over 80 liters per man per day), which is why most of the supply trucks are still carrying fuel.