The senior commanders of the US forces most directly involved in the ground part of any war with Iraq are said to fear the campaign could be a more protracted and bloody affair than some in the Pentagon's civilian leadership expect.
The Washington Post says Army chief General Eric Shinseki and General James Jones, commandant of the Marine Corps, are worried at excessive confidence that Iraqi resistance would speedily collapse after an invasion, and that President Saddam Hussein's removal would be a formality.
Neither man commented publicly on the reports yesterday. But Air Force General Richard Myers, the chairman of the Joint Chiefs of Staff and the Pentagon's most senior uniformed official, denied that current planning was based on assumption of an easy triumph.
General Myers said nobody at the Pentagon believed "this sort of endeavour, if we were asked to do it, would be a cakewalk". Paul Wolfowitz, the deputy Secretary of Defence and a prime civilian hawk on Iraq, also rejected charges that that the US had not been over-confident in its planning.
It would be a "terrible mistake" to predict how a war would unfold, he said, stressing that full account was being taken of the risk that President Saddam would unleash chemical or biological weapons against invaders.
But General Jones, who takes command of US forces in Europe next month, confirmed to the Post that he disagreed "with those who seem to think this is pre-ordained to be a very easy military operation".
The divisions reflect long-standing tensions between the civilian leadership under Donald Rumsfeld, the Defence Secretary, who from the outset has demanded that planners "think outside the box" in devising a blitzkrieg-like strategy to topple President Saddam quickly. Many uniformed commanders favour a more traditional approach, involving a much larger force, advancing more slowly on its objective, but projecting overwhelming force.
This latter camp includes General Tommy Franks, the chief of US Central Command, who would be in direct charge of a war against Iraq. He is said to have insisted that a force of 200,000 to 250,000 would be needed. This is admittedly far smaller than the half-million-strong coalition assembled for the 1991 Operation Desert Storm, which drove Iraqi forces from Kuwait.
But it is a far cry from the once-mooted "inside-out" operation aimed at Baghdad itself. This would rely on tactical surprise with a short, very fierce bombing campaign and commando strikes on suspected weapons of mass destruction and missile sites.
A welter of leaks over the past few months has given the impression that a compromise has emerged over the planning, which combines elements of both approaches.
The renewed argument over tactics has coincided with the first solid evidence of war preparations by the Iraqi regime and reported claims by US intelligence officials that President Saddam intends a "scorched earth" strategy in the face of an invasion.
Intelligence photographs show barriers have been put up on runways at a group of four remote air bases near oil pumping stations in Western Iraq. These installations could could be targets of the US, as it tried to take out potential missile launch sites which could be used against Israel in the initial stages of a war.
Officials say similar defensive measures are being taken at bases around Baghdad and in south-eastern Iraq. The barriers could be moved, Pentagon officials said, but their presence might be a cause for delay. "The bases are essentially unused, so you wouldn't want to bomb them then have to repair the runways," one said.
* Warplanes from a US-British operation patrolling southern Iraq fired on air defences in southern Iraq yesterday after Iraqi forces moved a mobile radar system into a "no-fly" zone, the US military said. It was the fourth attack in five days by aircraft monitoring the zone.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies