In Victory Misunderstood: What the Gulf War Tells Us About the Future of Conflict, Stephen Biddle (writing in 1996) explains that no one factor (e.g. superior Coalition technology or inferior Iraqi morale) clearly explains the amazing outcome of the (first) Gulf War:
In less than six weeks, 795,000 Coalition troops destroyed a defending Iraqi army of hundreds of thousands, losing only 240 attackers. This loss rate of fewer than one fatality per 3,000 soldiers was less than one tenth of the Israelis’ loss rate in either the 1967 Six-Day War or the Bekaa Valley campaign in 1982, less than one twentieth of the Germans’ in their blitzkriegs against Poland or France in 1939-40, and about one one-thousandth of the U.S. Marines’ in the invasion of Tarawa in 1943.
Some of Iraq’s tactical shortcomings:
First, Iraqi defensive positions were very poorly prepared. The “Saddam line” at the Saudi border was haphazard at best (although given the poor quality of its conscript garrison, it is unclear how significant this was). More important for the outcome, the Republican Guard blocking positions were no better Western armies dig their fighting positions into the earth below grade, and hide the soil removed in excavation. The Guard, on the other hand, simply piled sand into loose berms, or mounds, on the surface of the ground around combat vehicles and infantry positions. This gave away the defenders’ locations from literally thousands of meters away, as the berms were the only distinctive feature of an otherwise flat landscape, without providing any real protection against the fire this inevitably drew. Loose piles of sand cannot stop modern high-velocity tank rounds. In fact, they barely slow them down. U.S. crews in 73 Pasting reported seeing 120 mm tank rounds pass through Iraqi berms, through the Iraqi armored vehicle behind the berm, and off into the distance. No U.S. tank crew would leave itself so exposed.
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Second, the Republican Guard failed to coordinate the efforts of the different arms at its disposal. In particular, artillery support was almost wholly absent, both in defense against American assaults and in support of the Guard’s own counterattacks. The Iraqis made some attempt to direct artillery against the advancing Americans, but proved unable either to adjust fire against moving targets (a difficult task) or even to deliver fire in mass against fixed points as Americans moved past them (an easier job).
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Third, Iraqi covering forces systematically failed to alert their main defenses of the U.S. approach, allowing even Republican Guard units to be taken completely by surprise. Going back at least as far as World War I, all Western armies have used covering forces — whether observation posts, forward reconnaissance screens, or delaying positions — to provide warning to the main defenses that they are about to be attacked. Ideally, these covering forces serve other functions as well (such as stripping away the opponent’s recon elements, slowing the attacker’s movement, or channeling the assault), but the minimum function they must perform is to notify the main defense of an attacker’s approach. This is not difficult. A one-word radio message is enough to sound the alarm. Even less can work if commanders agree in advance that failure to check in at specified times will be taken as warning of attack. The brevity of the message makes it virtually impossible to jam; the procedural backup of interpreting silence as warning means that even a dead observer can provide an alert.
Biddle’s analyis — including computer simulations — shows that avoiding those blunders could have neutralized many of the Coalition’s otherwise overwhelming advantages.