The army, the source of the latest complaints, has long been pitted against the air force in a competition for influence over the future direction of US military almost since the invention of the airplane.

But this is the first war in which a US military campaign has been designed to take maximum advantage not only of US dominance in the air, but of information technologies and advances in airborne surveillance and reconnaissance on the ground as well as the air.

As such, it is putting to the test theories that a smaller ground force, operating in close coordination with air power and with greater visibility of the battlefield, can project the power of a much larger conventional force.

"There are huge stakes here in terms of which service commands the larger budget share, which service is the most prestigious, which service's four stars get the most important commands," Andrew Bacevich, a retired army officer and Boston University professor, said Monday,

But the intensity of the debate also is due to deeply held convictions about the nature of warfare with the army taking a more skeptical view of the promise of high technology than other services, he said.

On the one hand are those, he said, "who think that the nature of war is immutable and that war is a highly risky proposition, almost uncontrollable, in that when victories are won they are won through the application of superior power."

On the other side are those who believe that "the nature of war can be shaped, that today there is a particular opportunity to shape it with information technology and precision weaponry and that this transformed war, this revolutionary war has the potential to make force far more politically useful and even humane," he said.

US Defense Secretary Donald Rumsfeld has intensified the struggle by pushing the army, in particular, to abandon its tank heavy Cold War force structure and replace it with lighter, faster deploying forces.

Last year, he infuriated its leaders by cancelling a program to develop and field its 11-billion dollar Crusader artillery system on grounds that it was too heavy to deploy quickly.

In Afghanistan, he opted to use special operations forces and air power to rout the Taliban, bringing in conventional ground forces only after most of the country had fallen to Afghan rebel forces.

Even before Rumsfeld, though, the army was struggling to maintain its relevance in a world of unexpected wars in far-flung places.

President Bill Clinton ruled out the use of ground forces in Kosovo, relying exclusively on air power to bring down the regime of Slobodan Milosevic in the former Yugoslavia.

The army did not help its case when it took a month to deploy a task force of AH-64 Apache helicoptes to Albania. The low-flying attack helicopters were never used because of fears that they were too vulnerable to Serb ground fire.

But with a major ground war underway now, the army's supporters are pointing to Iraq as vindication of the service's traditional approach to warfare and its pleas for more divisions to handle contingencies from the Middle East to Korea.

"Lot of people said tanks are outdated, we don't need any more," said retired army Lieutenant General William Odom. "The idea of lightening (those) heavy forces, getting rid of those is, to put it politely, unwise."

When fast moving tank columns outran their supply lines, anonymous army officials accused Rumsfeld of not deploying enough forces to the region, saying he was trying to fight the war "on the cheap."

"The retired army officers who are complaining are the same people who all along have been complaining that the active force is too small and you need more boots on the ground," said James Carafano, an expert at the Center for Strategic and Budgetary Assessments, a Washington research group.

"The campaign has not been going on long enough to make the kind of criticisms they have been making," he said.

Bacevich said the results so far have been mixed with dramatic advances on the ground offset by stiffer-than-expected resistance and unfulfilled hopes for a quick collapse of the regime.

"The commanders on the ground don't care about the theological arguments," he said. "The commanders on the ground are trying to figure out how to accomplish their mission with minimum damage to their own force, and the circumstances are ones that call for a more deliberate campaign."

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