Soldiers on the ground, as well as psychologists, war veterans and defense analysts, believe morale could be dented in a conflict tougher and longer than military planners expected.

Some say that within a month, the invaders could be at breaking point.

As the war heads toward the end of its second week, psychologist Dr John Potter said: "The maximum I would ever like to see anyone in combat is 40 days.

"After that you get serious problems. Everybody eventually has their limits," said Potter, who taught military psychology at Britain's Sandhurst military academy for eight years.

He said British troops had been trained to face urban guerrilla fighting in Northern Ireland but the Middle East piled on new challenges, including potential suicide attacks.

"Now you have everything in one scenario. You also have an enormous propaganda war like you have never seen before."

U.S. Marines in the desert certainly agree that conditions are tough. They do not think much of the view across the desert, miss their families and worry about being killed.

"I feel like the longer I'm out here, the less are my chances of staying alive," U.S. Marine Lance-Corporal Michael Sanchez told Reuters correspondent Matthew Green.

"This was supposed to be one of the quickest wars," complained Lance-Corporal Dennis Coats. "We weren't anticipating getting attacked so early. We weren't anticipating all this terrorist activity."

Defense analyst Mike McGinty from the Royal United Services Institute saw Iraq as a deadly battlefield where no one is safe.

"The whole of Iraq has essentially become a potential killing zone. There is never any moment when the troops have real security from anything," he said.

REST & RELAXATION

Exhaustion is another factor with constant action a major drain on soldiers' personal resources.

Britain's Army chief Mike Jackson put it succinctly after the blitzkrieg start to the war: "Armies cannot move forever without stopping from time to regroup, to ensure that their supplies are up, and even -- believe it or not -- soldiers need a bit of sleep from time to time."

Britain and the United States insist morale is high among their fighting forces and that the campaign is going to plan.

But Potter wondered if the cracks might be showing on the battlefield, pointing out that most British casualties have been hurt in accidents, or have been victims of their U.S. allies.

"What really is concerning people is a potential split between the British and the Americans over friendly fire," Potter said.

"The worry is that our own morale could be reduced by the perception that (the British) are dealing with cowboys."

Twelve years on from the war to liberate Kuwait from Iraqi occupation, veterans are quick to praise today's soldiers.

"They are having a damn sight tougher time than we did," said Tony Flint of the Gulf Veterans and Families Association. "This time we will end up with a damn sight more casualties."

Twenty-six British troops have already been killed in Iraq compared to 24 in the whole of the 1991 conflict.

Flint argued U.S. commanders had gone about their campaign too quickly, overstretching supply lines.

"From the human perspective of being a soldier, you cannot keep up that pace for too long," he said.

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