This confidence in American strength rests, however, on certain paradoxes. While Americans are proud of their military, this feeling is not entirely reciprocated. While the Iraq war demonstrated American military supremacy, it also laid bare how blunt that weapon can be. And, above all, the very display of strength against their enemies which Americans have required since 9/11 may provoke new dangers of the kind the nation has been fighting to prevent.

I was in Washington after lecturing at West Point on how warfare has changed since the Second World War. All the officers and cadets I spoke to could not have been more polite or have appeared more interested, but the culture gap appeared wider than ever. I urged them to step outside themselves. As tactfully as possible, I tried to explain that many foreigners saw their country not as “the land of the brave and the home of the free”, but as the source of a contagious junk culture devoted to self-indulgence and Hollywood fantasy.

The Bush Administration may believe in exporting American democratic and business values, using the US Army and Marines where necessary. But there is a tension between the cultures of the US military and the rest of America which mirrors the relationship between the US and the rest of the world.

The Pentagon commentator Thomas Ricks has pointed out in his book, Making the Corps, that many in the US military despise their own country’s civilian values. Rather like anti-American critics abroad, they see modern America as a decadent and selfish society, utterly lacking in self-discipline. The US Marine Corps even goes through phases of believing that the next war is going to be fought at home, with the slums of Los Angeles resembling Mogadishu.

At West Point I had the opportunity to explore further what sets the American warrior caste apart. The Iraq war pointed up some of the clear differences between the operational procedures of the US Army and the British Army. The American advance to Basra had demonstrated their undoubted strength in “force-on-force” operations. Iraqi forces simply melted away. But US troops had clearly received no training or preparation for the stabilisation phase, which was bound to follow. They did not even know how to set up proper road-blocks to check vehicles and prevent suicide attacks. Most striking of all, they seemed to want to keep the Iraqis they had come to liberate at arm’s length.

The moment the British had secured Basra, the order went out to remove helmets so that the local Iraqis could see human faces. It was a technique tried and tested in Northern Ireland. The American officers looked uncomfortable. They said that their troops could not possibly do that. It contravened fundamental instructions: soldiers were not allowed to remove helmet or body armour when on active service. “But don’t you see,” I said to a colonel in the Rangers, “that your helmets, sunglasses and body-armour make you look like imperial stormtroopers out of Star Wars?” To his credit, he acknowledged that that was probably the case. But the idea did not seem to have occurred to them that on peace-enforcement operations, you cannot have effective intervention without human interaction.

Soon after the US intervention in Bosnia in 1995 the American military thinker Edward Luttwak compared the role of peacekeeping forces with heavily armoured Roman legionaries on the borders of the civilised world keeping the barbarians at bay — even though terrorism had proved that we were living in a world without frontiers. It was also the time of the hi-tech/low-bodybag war, policing the new world disorder from the air or with missiles fired from distant warships. Just before operations in Kosovo began, General Morillon, a former French commander in Bosnia asked: “Who are these soldiers who are ready to kill but not to be killed?”

Nowhere does this hands-off approach create greater resentment than in the Arab world, where hi-tech warfare is seen as arrogant and cowardly. This Arab resentment is the military counterpart to the Islamic and Third World loathing of globalisation. Western armies are, of course, unapologetic. US tank units in the Gulf even adopted the AT&T advertising slogan — “Reach out and touch someone” — to boast of their superior range in weaponry.

It is hard for the US Armed Forces to accept that their crushing defeat of Saddam Hussein may prove a dangerous victory. For the Arab world, the only possible challenge to the total supremacy of the United States can come in the form of terrorist acts, what the Pentagon now defines as “asymmetrical warfare”. Islamic fundamentalists will not compromise in the struggle against “the Great Satan”. They reject official diplomacy just as they reject the idea of secular government. And any Arab leaders prepared to negotiate with the Americans or Israelis are liable to be assassinated. I fear that the asymmetrical power of the United States, however benignly intended, cannot avoid asymmetrical war.

The author’s Berlin The Downfall 1945 is published by Penguin.

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