In the Gulf War in 1991, high-precision weapons - smart bombs and cruise missiles hitting their targets with unerring accuracy - appeared to rule the battlefield. Television viewers around the world saw telecommunication buildings in Baghdad erupt in flames on the first night of the war as they were hit by smart bombs. General Norman Schwarzkopf, the allied commander, proudly showed film of an American plane hitting an Iraqi mobile Scud missile launcher.
It never happened; or at least it was highly exaggerated. A post-war study by the CIA of 90 scud missile launchers, claimed destroyed by the US air force in Iraq's western desert, showed that the real figure was nil. The pilots had been hitting decoys and petrol trucks on the road to Jordan.
Iraq lost some 2,500 tanks in the war, but a study by US specialists of a sample of these showed that just 10 per cent had been destroyed from the air. The rest were mostly abandoned by their crews.
This means that "punishing Saddam", the glib recommendation of US Congressional leaders is far more difficult than it looks. "In the war we had real difficulty in hitting priority targets like Saddam himself, tanks, artillery, the Republican guard divisions and the troops withdrawing from Kuwait to Basra," says one US expert.
This view is supported by a highly critical report by the General Accounting Office (GAO) a monitoring arm of the US Congress. Entitled "Operation Desert Storm; evaluation of the Air Campaign", it was published this summer in the teeth of objections from the Pentagon.
It systematically deflates the claims, made by manufacturers and the US Department of Defence alike, for the effectiveness of most weapon systems.
An advertisement for General Dynamics advertising its F16 fighter-bomber reads: "No matter what the mission, air-to-air, air-to-ground. No matter what the weather, day or night, the F16 is the premier dog fighter."
In fact, the GAO notes sourly, the ability of the F16's air-to-ground Maverick missile costing $100,000 (pounds 61,000) each, to hit anything was impaired or sometimes made impossible by clouds, haze, humidity, smoke and dust. It is even more dismissive of the much-vaunted Stealth bomber.
The picture that emerges of the air war is that the US and its allies were able to hit multi-storey buildings and other large, immobile targets with accuracy. Thus US planes hit telecommunications towers, the oil refinery and power station at Doura on the capital's southern outskirts as well as bridges spanning the Tigris. But it could not destroy smaller, more mobile targets such as tanks and artillery pieces.
If the air war is restarted by President Clinton the same pattern is likely to be repeated. The civilian infrastructure is easy to hit, but not the military and security apparatus which have secret and frequently changed headquarters. There could be less tolerance of Iraqi civilian casualties in the West than there was in 1991.
There is a further problem for the US. The Gulf War got Americans used to the idea that an air campaign could be waged with almost no casualties. This did not happen purely because of high precision weapons. The GAO report notes that "after two F-16 losses on day three [of the war] in the Baghdad area" the aircraft were no longer used in large numbers in the metropolitan area of the capital.
This inability, because of losing planes and pilots, to operate at low altitudes put a severe cramp on what the US can do against Iraq. For instance, moving tanks cannot be hit without risking US casualties.
The misrepresentation of what happens in the skies above Iraq is motivated by more than military braggadocio. At the time of Desert Storm, the US had 229 aircraft capable of delivering laser guided munitions. That figure has now risen to 500 planes. But such guided weapons are vastly more expensive than ordinary bombs and missiles. The US services have now bought, or are acquiring, guided munitions worth no less than $58bn (pounds 35bn).
This immense investment is in the face of the conclusion of the GAO that "the air campaign data did not validate the purported efficiency or effectiveness of guided munitions."
At the same time, however, Iraq is largely defenceless unless US and allied aircraft attack at low altitude. Its people are weary after seven years of economic siege. They remember the incompetence of their own government in 1991.
It failed to stockpile any petrol, kerosene or diesel so when the oil refineries were hit, all transport ground to a halt because of a fuel shortage.
No wonder Iraqis with cars have been queuing this week to fill up at petrol stations. But no wonder also that President Clinton is so cautious about ordering his planes to attack.