A pulsating, minute-long roar of sound brought President George W Bush's crusade against "terrorism" to Baghdad. There was a thrashing of tracer on the horizon from the Baghdad air defences and then a series of tremendous vibrations that had the ground shaking under us, the walls moving, the sound waves clapping against our ears.

Tubes of fire tore into the sky around the Iraqi capital, dark red at the base, golden at the top. Looking out across the Tigris from the river bank, I could see pin-pricks of fire reaching high into the sky as America's bombs and missiles exploded on to Iraq's military and communication centres and, no doubt, upon the innocent as well.

Valhalla, I said to myself. This needed Wagner, the twilight of the gods, Götterdämmerung. No one in Iraq doubted that the dead would include civilians. Tony Blair had said just that in the House of Commons debate that very same week.

But I wondered, listening to this storm of fire across Baghdad, if he had any conception of what it looks like, what it feels like, or of the fear of those Iraqis who were, as I wrote my report an hour later, cowering in their homes and basements. Just before the missiles arrived, I talked to an old Shia Muslim woman in a poor area of Baghdad, dressed in traditional black with a white veil over her head. I pressed her for what she felt. In the end, she just said: "I am afraid." The explosions now gave expression to her words.

Donald Rumsfeld was to assert that the American attack on Baghdad was "as targeted an air campaign as has ever existed". But he could not have told that to five-year-old Doha Suheil. She looks at me on the first morning of the war, drip-feed attached to her nose, a deep frown over her small face as she tries vainly to move the left side of her body. The cruise missile that exploded close to her home in the Radwaniyeh suburb of Baghdad blasted shrapnel into her legs - they were bound up with gauze - and, far more seriously, into her spine. Now she has lost all movement in her left leg. Her mother bends over the bed and straightens her right leg, which the little girl thrashes around outside the blanket. Somehow, Doha's mother thinks that if her child's two legs lie straight beside each other, her daughter will recover from her paralysis. She was the first of the patients brought to the Mustansariya College Hospital after America's blitz on the city began.

There is something sick, obscene, about these hospital visits. We bomb. They suffer. Then we reporters turn up and take pictures of their wounded children. The Iraqi Minister of Health decides to hold an insufferable press conference outside the wards to emphasise the "bestial" nature of the American attack. The Americans say that they don't intend to hurt children. And Doha Suheil looks at me and the doctors for reassurance, as if she will awake from this nightmare and move her left leg and feel no more pain.

So let's forget, for a moment, the cheap propaganda of the regime and the cocky moralising of Messrs Rumsfeld and Bush, and take a trip - this bright morning in March 2003 - around the Mustansariya College Hospital. For the reality of war is ultimately not about military victory and defeat, or the lies about "coalition forces" which our "embedded" journalists were already telling about an invasion involving only the Americans, the British and a handful of Australians. War, even when it has international legitimacy - which this war does not - is primarily about suffering and death.

Take 50-year-old Amel Hassan, a peasant woman with tattoos on her arms and legs, who now lies on her hospital bed with massive purple bruises on her shoulders - they are now twice their original size. She was on her way to visit her daughter when the first American missiles struck Baghdad. "I was just getting out of the taxi when there was a big explosion and I fell down and found my blood everywhere," she told me. "It was on my arms, my legs, my chest."

Amel Hassan still has multiple shrapnel wounds in her chest. Her five-year-old daughter Wahed lies in the next bed, whimpering with pain. She had climbed out of the taxi first and was almost at her aunt's front door when the explosion cut her down. Her feet are still bleeding, although the blood has clotted around her toes and is stanched by the bandages on her ankles and lower legs. Two boys are in the next room. Saad Selim is 11, his brother Omar 14. Both have shrapnel wounds to their legs and chest.

Isra Riad is in the third room with almost identical injuries, in her case shrapnel wounds to the legs, sustained when she ran in terror from her house into her garden as the blitz began. Imam Ali is 23 and has multiple shrapnel wounds in her abdomen and lower bowel. Najla Hussein Abbas still tries to cover her head with a black scarf, but she cannot hide the purple wounds to her legs. Multiple shrapnel wounds. After a while, "multiple shrapnel wounds" sounds like a natural disease, which I suppose - among a people who have suffered more than 20 years of war - it is.

So was all this, I asked myself, for 11 September 2001? Was all this to "strike back" at our attackers, albeit that Doha Suheil, Wahed Hassan and Imam Ali had nothing - absolutely nothing - to do with those crimes against humanity, any more than had the awful Saddam? Who decided, I wondered, that these children, these young women, should suffer for September 11th?

Driving across Baghdad was an eerie experience. The targets were indeed carefully selected, even though their destruction inevitably struck the innocent. There was a presidential palace with four 10m-high statues of the Muslim warrior Saladin on each corner - the face of each, of course, was Saddam's - and, neatly in between, a great black hole gouged into the façade of the building. The Ministry of Air Weapons Production was pulverised, a massive heap of prestressed concrete and rubble. But outside, at the gate, there were two sandbag emplacements with smartly dressed Iraqi soldiers, rifles over the parapet, ready to defend their ministry from the enemy that had already destroyed it.

The morning traffic built up on the roads beside the Tigris. No driver looked too hard at the Republican Palace on the other side of the river, or the Ministry of Armaments Procurement beside it. They burned for 12 hours after the first missile strikes. It was as if burning palaces and blazing ministries and piles of smoking rubble were a normal part of daily Baghdad life. But then again, no one under Saddam's regime would spend too long looking at such things, would they?

Iraqis were puzzled as to what all this meant. In 1991, the Americans struck the refineries, the electricity grid, the water pipes, communications. But on day two of this war, Baghdad could still function. The land-line telephones worked, the internet operated, the electrical power was at full capacity, the bridges over the Tigris remained unbombed. My guess was that when - "if" was still a sensitive phrase - the Americans arrived in Baghdad, they would need a working communications system, electricity, transport. What had been spared was not a gift to the Iraqi people, I concluded; it was for the benefit of Iraq's supposed new masters. How wrong I was.

The Iraq Daily emerged with an edition of just four pages, a clutch of articles on the "steadfastness" of the nation - steadfastness in Arabic is soummoud, the same name as the missiles Iraq partially destroyed before Bush forced the UN inspectors to leave by going to war - and a headline that read: "President: Victory Will Come in Iraqi Hands". During the bombing on Friday night, Iraqi television - again, there had been no attempt by the US to destroy the television facilities - showed an Iraqi general, appearing live, to reassure the nation of victory. As he spoke, the blast waves from cruise missile explosions blew in the curtains behind him and shook the television camera.

So where did all this lead us? In the early hours of the next day, I looked once more across the Tigris at the funeral pyre of the Republican Palace and the colonnaded ministry beside it. There were beacons of fire across Baghdad and the sky was lowering with smoke. The buttressed, rampart-like palace - sheets of flame soaring from its walls - looked like a medieval castle ablaze.

That second afternoon, the Iraqis lit massive fires of oil around Baghdad in the hope of misleading the guidance system of the cruise missiles. Smoke against computers. The air-raid sirens began to howl again just after 6.20pm on 22 March, when Saddam's biggest military office block, a great rampart of a building 20 storeys high beside his palace, simply exploded in front of me, a cauldron of fire, a 100ft sheet of flame and a sound that had my ears singing for an hour afterwards. The entire, buttressed edifice shuddered under the impact. Then four more cruise missiles came in. It was the heaviest bombing Baghdad had suffered in more than 20 years of war.

To my right, a long colonnaded building looking much like the façade of the Pentagon coughed fire as five missiles crashed into the concrete. In an operation officially intended to create "shock and awe" - Rumsfeld's latest slogan - shock was hardly the word for it. The few Iraqis in the streets around me - no friends of Saddam, I would suspect - cursed under their breath.

From high-rise buildings, shops and homes came the thunder of crashing glass as the shock waves swept across the Tigris in both directions. Minute after minute the missiles came in. Many Iraqis had watched - as I had - the television tape of those ominous B-52 bombers taking off from Britain only six hours earlier. Like me, they had noted the time, added three hours for Iraqi time ahead of London and guessed that, at around 9pm, the terror would begin. The B-52s, almost certainly firing from outside Iraqi airspace, were dead on time.

Policemen drove at speed through the streets, their loudspeakers ordering pedestrians to take shelter or hide under cover of tall buildings. Much good did it do. Crouching next to a block of shops, I narrowly missed the shower of glass that came cascading down from the upper windows as the shock waves slammed into them.

A few Iraqis - husbands and wives, older children - could be seen staring from balconies, shards of broken glass around them. Each time one of the great golden bubbles of fire burst across the city, they ducked inside before the blast wave reached them. As I stood beneath the trees on the corniche, a wave of cruise missiles passed low overhead, the shriek of their passage almost as devastating as the explosions that were to follow. How, I asked myself, does one describe this outside the language of a military report, the definition of the colour, the decibels of the explosions? The flight of the missiles sounded as if someone was ripping to pieces huge canopies of silk across the sky.

There is something anarchic about all human beings, about their reaction to violence. The Iraqis around me stood and watched, as I did, the tongues of flame bursting from the upper storeys of the building beside Saddam's palace, reaching high into the sky. Strangely, the electricity grid continued to operate, and around us the traffic lights continued to move between red and green. Billboards moved in the breeze of the shock waves; floodlights continued to blaze on public buildings. Above us, curtains of smoke were moving over Baghdad, white from the explosions, black from the burning targets. How could one resist this? How could the Iraqis ever believe - with their broken technology, their debilitating 12 years of sanctions - that they could defeat the computers of these missiles and of these aircraft? It was the same old story: irresistible, unquestionable power.