A century hence, people will still be reading the speech written by Lieutenant-Colonel Tim Collins, the 42-year-old commander of The Royal Irish battle group, which he delivered to his troops in Kuwait on Wednesday afternoon, just hours before they went into battle. Colonel Collins has a history degree, but does not look like a poet. Readers of The Times will have seen his photograph, in shades and combat gear, a cigar clamped between his teeth. He has the air of a Rambo, but the literary touch of a Rimbaud.

Imagine you are in the Kuwaiti desert, your face sandpapered raw, scared to your bowels and stoned on adrenalin, knowing you are about to fight, and kill, or die. And hear this:

“THE enemy should be in no doubt that we are his Nemesis and that we are bringing about his rightful destruction. There are many regional commanders who have stains on their souls and they are stoking the fires of Hell for Saddam. As they die they will know their deeds have brought them to this place. Show them no pity. But those who do not wish to go on that journey, we will not send. As for the others, I expect you to rock their world.

“We go to liberate, not to conquer. We will not fly our flags in their country. We are entering Iraq to free a people, and the only flag that will be flown in that ancient land is their own. Don’t treat them as refugees, for they are in their own country.

“I know men who have taken life needlessly in other conflicts. They live with the mark of Cain upon them. If someone surrenders to you, then remember they have that right in international law, and ensure that one day they go home to their family. The ones who wish to fight, well, we aim to please. If there are casualties of war, then remember, when they woke up and got dressed in the morning they did not plan to die this day. Allow them dignity in death. Bury them properly, and mark their graves.

“You will be shunned unless your conduct is of the highest, for your deeds will follow you down history. Iraq is steeped in history. It is the site of the Garden of Eden, of the Great Flood, and the birth of Abraham. Tread lightly there. You will have to go a long way to find a more decent, generous and upright people than the Iraqis. You will be embarrassed by their hospitality, even though they have nothing ...

“There may be people among us who will not see the end of this campaign. We will put them in their sleeping bags and send them back. There will be no time for sorrow. Let’s leave Iraq a better place for us having been there. Our business now, is north.”

The words of Colonel Collins will long survive this war, for in their raw clarity, they capture its essence, and a military sensibility that is peculiar to our time. In sharp contrast to the gusts of war rhetoric from politicians we have been hearing for the past month, Collins spoke of history, family, respect, dignity, and the individual moral choice between killing justly, and just killing. Saddam may merit the fires of Hell, but Collins’s men will also remember the ordinary man who got dressed this morning in tattered Iraqi uniform, with a culture older than ours.

Collins’ oration echoes the King James Bible, but it is also the language of the Playstation: rock their world. It comes without demons, or plastic martyrs; he does not promise Dulce et decorum, but sharp modern irony: we aim to please. Put out fewer flags, he urged them, and tread lightly. This is precisely the reverse of the battlefield oratory used to motivate British troops a century ago.

The language of war was changed forever by the First World War. Before 1914, battle rhetoric strictly followed the cadences of Henry V and Henry Newbolt: “We few, we happy few”; “Play up and play the game.” But after four years of carnage, the holy abstractions of honour, patriotism and duty, framed into set-piece epitaphs by Rudyard Kipling and carved on numberless gravestones, seemed grotesque.

“I was always embarrassed by the words ‘sacred’, ‘glorious’, and ‘sacrifice’,” wrote Ernest Hemingway in A Farewell to Arms. “Abstract words such as ‘glory’, ‘honour’, ‘courage’ or ‘hallow’ were obscene beside the concrete names of villages, the numbers of regiments and the dates.”

The language of the Second World War was more honest, but it still harked back to an ancient tradition of patriotic warrior poetry, while introducing the grim dishonesty of military euphemism, memorably lampooned by Joseph Heller in Catch-22, that continues in such cowardly combinations as “collateral damage” (dead people) and “target-rich environments” (lots of dead people).

Collins, by contrast, spoke in an emotive modern vernacular: ferocious, but also slangy, ironic, and gentle. God and country are there, but in undertone. The valour lies not in bloodshed, but in decency; not in winning, but in leaving well. And at its heart, his speech offers this unlikely truth: that war is not glorious, or fun, but complicated and morally messy; not a matter of sacred shrouds, poppy fields and noble deaths, but of dead friends, wrapped in sleeping bags.

Millions of war words will be spilled in the coming weeks, but none more powerful than these. Perhaps Collins does not know it (Lincoln genuinely thought few would remember his speech at Gettysburg), but he has written a simple and stirring prose-poem for the 21st-century soldier.

You will have to go a long way to find a more decent, generous and upright evocation of what modern war means.

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