None of the shortages and delayed resupply efforts got any American troops killed. Anything like that would have been picked up by one of the 700 embedded journalists and turned into screaming headlines. But the troops were not happy with the shortages of fuel, food, spare parts and even ammunition. These problems slowed some units down and caused discomfort among the troops and lots of headaches for their officers. Congress and the media will make much about the problems encountered.
Fixing the problems is another matter. Logistics is a business of large numbers. For each soldier sent to a combat zone, you have to send at least a few tons of stuff along with him just to get him started. It's a lot more stuff it a heavy force (armored vehicles) in involved. Here we're talking over a hundred tons per trooper. And to keep each soldier fighting, it's going to take up to half a ton of newly delivered stuff per day. The air force does not have the transports to do it by air, unless you are fighting an Afghanistan style battle where your total ground force is less than 300 guys (the number of Special Forces and CIA paramilitaries in Afghanistan during the time it took to overthrow the Taliban.) So you have to move material by ship. That takes time, and you need ports to unload it quickly, places to park it, trucks to carry it to the troops and roads to move over. This is where the old military saying, "amateurs talk about tactics, professionals talk about logistics," comes from. There are no easy solutions.
An examination of the American logistical effort in Iraq revealed some embarrassing shortcomings. There were a lot of shortages and confusion in keeping track of supplies. It was expected that lessons learned from the 1990-91 Desert Storm operation, and new technology, would have eliminated most of these problems. But because the 2003 campaign was a lot different than the earlier one, such was not the case. In 1991, the United States had use of larger port and base facilities in Saudi Arabia. The Saudis had invested billions of dollars in these facilities, in case it might have to call on American military assistance when threatened by a stronger neighbor (Iraq and Iran being the most feared.) Kuwait had nothing like the Saudi facilities, and this made the American logistical effort much more difficult. But the biggest problem was that the fighting in 2003 was much more intense and fast moving than what took place in 1991. In 2003, most divisions marched, and often fought, nearly over 600 kilometers in 23 days. That's a remarkable campaign by any standard compared to other operations in the past century. In 1941, some German divisions advanced 700 kilometers into Russia in 29 days, and in 1944, some Allied divisions largely pursued retreating Germans 880 kilometers across France in 32 days, but both of these were seen as very exceptional cases. While the divisions in 1991 had about 30 days worth of supplies available to them in Saudi bases, the 2003 units only had 5-6 days worth. Worse, the 2003 Iraq advance was led by hundreds of M-1 tanks, that require about three gallons of fuel for each kilometer they move. But the biggest problem was the unexpected speed of the advance. The original plan called for it taking about 125 days to advance on Baghdad and take it. Good military planning always starts with the worst case, and 125 days of fighting was as bad as anyone thought it could get. The coalition force was well trained, professional and well led, and prepared to take advantage of enemy mistakes and weaknesses. Thus the ability to quickly turn the 125 day plan into a 23 day one. But this caused most of the logistical problems encountered. There simply were not enough trucks, supply dumps and support troops to support the 23 day campaign in as timely and sufficient manner as the original 125 day plan.