From the Washington Times, October 7, 2007:
Arnaud de Borchgrave - Watching them drive by at 30 miles per hour, would take 75 days. Bumper-to-bumper, they would stretch from New York City to Denver. That's how U.S. Air Force logistical expert Lenny Richoux described the number of vehicles that would have to be shipped back from Iraq when the current deployment is over. These include, among others, 10,000 flatbed trucks, 1,000 tanks and 20,000 Humvees.And this assumes no unpleasant surprises, and no war with Iran.
Even in an emergency, said Col. Richoux in DefenseNews, the evacuation of 162,000 troops in 23 ground combat brigades and millions of tons of equipment would take some 20 months. Military shipping containers, end to end, would stretch from New York City to the gates of the U.S. Military Academy at West Point.
The main resupply route for convoys that runs 344 miles from Kuwait (skirts Basra to the north) to Baghdad is already under the constant threat of hit-and-run insurgency attacks, including improvised explosive devices. Driving empty, on their way back to pick up another load in Kuwait, convoys are just as vulnerable.
According to the Government Accountability Office (GAO), the military has some 300,000 "heavy" items that would have to be shipped back, such as ice-cream machines that churn out different flavors upon request at a dozen bases throughout the California-size country. And before it can be loaded onto ships, equipment has to be scrubbed clean to conform to U.S. Agriculture Department regulations. The U.S. maintains some 200 wash points in Kuwait. Helicopters have to be shrinkwrapped.
Clearly any major withdrawal from Iraq would have to be a phased operation and some equipment would have to be destroyed or transferred to the new Iraqi army. Since the first Gulf war (1990-91), the U.S. Military Sealift Command has acquired a fleet of 18 large, roll-on/roll-off ships, each nearly the size of an aircraft carrier, capable of carrying more than 300,000 square feet of cargo. Eight of these ships are normally assigned to MSC's Afloat Prepositioning Ship Squadron, loaded with Army equipment and supplies in the Indian Ocean theater ready to meet up with troops flown in to an emergency situation in the Gulf region.
MSC cargo ships make regular runs to Iraq from San Diego and Jacksonville, Fla. For the first two years of the war, units were rotated in and out of theater with all their equipment. Thus, the 5,200-strong 3rd Armored Cavalry Regiment's equipment — 300 armored vehicles, 57 aircraft, 900 trucks and Humvees — made the trip from Fort Carson to Kuwait three times before the Pentagon changed back to the Gulf war I and Vietnam War system of leaving the heavy stuff for the incoming replacement unit.