Air power played a critical role in the war
At the start of the air war in Iraq, US Defence Secretary Donald Rumsfeld asserted that this would be as precise a campaign as there has ever been - and quite unlike the mass bombings of World War II.
For all sorts of reasons, it has also been strikingly different from the 1991 Gulf air war.
There is still fighting under way, and it is too early to draw firm conclusions.
There were obvious mistakes - including a spate of "friendly-fire" incidents - and, despite all the protestations about precision, there have been an unknown number of civilian casualties.
But, with the air war itself winding down, some analysts are already suggesting that air power may have had a more significant impact even than it did 12 years ago - particularly in wrecking Iraq's command and control capabilities and the ability of its army to put up a coherent defence when US ground forces arrived on the scene.
It could be a powerful endorsement of what air war strategists call "effects-based doctrine" - the combination of intelligence, targeting, and "smart" weaponry to strike at critical parts of an enemy's infrastructure.
It's a doctrine that has critics still, even within the Pentagon.
Whatever the truth, some of the differences compared to 1991 appear remarkable - at least at first glance.
1991 air war on Iraq
40,000 strike sorties
265,000 bombs dropped
2003 air war in Iraq
15,500 strike sorties
27,000 bombs dropped
So far this time, there have been a third of the number of sorties and a tenth of the bombs dropped as compared to the 43-day operation in 1991.
The proportion of smart weapons used is much greater now - about 67% compared to 7-8% in 1991 - but the total number of weapons - even smart weapons - this time is actually lower than before, at about 18,000.
Such statistics don't tell the whole story. There were many other elements that were different this time.
For one thing, even the smart bombs were very different, including many satellite-guided bombs and missiles. There were none in 1991.
Also, since 1991, Iraq has been subject to a long low-level air war through the enforcement of the no-fly zones.
In 1991, there was a much more wide-ranging bombing campaign against Iraq's general infrastructure. This time, the focus was very much more on ┐regime targets" and the Iraqi military, which was itself only half the size it was in 1991.
The Pentagon statistics on smart weapons in the air war do not include the large number of missiles and rockets fired by the many US helicopter gunships deployed to Iraq.
Some Pentagon officials say it was the network of surveillance, targeting and technology which was decisive, and the combination of air and ground forces which was better this time than ever before.
The destruction of Iraq's command and control by air power meant the Iraqi leadership could not really respond to the US military's rapid advances on the ground, while the US-led air forces also softened up the Iraqi forces for the US army and marines.
There was a glimpse of this combination of air and ground forces in the latter stages of the Afghanistan conflict. But it was largely absent from Kosovo just four years ago. And in the last Gulf War, the short ground war came only after more than five weeks of bombing.