US Defence Secretary Donald Rumsfeld forced his military chiefs to accept his idea that a relatively small, lightly armed force should go to war with Iraq, it is being alleged.
Rumsfeld overruled Franks, the magazine says
The New Yorker magazine quotes unnamed Pentagon sources as saying that Mr Rumsfeld insisted at least six times before the conflict on the proposed number of troops being reduced.
In an article to be published on Monday, the magazine says Mr Rumsfeld overruled advice from the war commander, General Tommy Franks, to delay the invasion of Iraq.
The defence secretary has flatly denied overriding military commanders.
"You will find, if you ask anyone who has been involved in the process in the central command, that every single thing that they have requested has, in fact, happened," he said on the US television network, Fox News.
The BBC's correspondent in Washington, Justin Webb, says Mr Rumsfeld is a famously abrasive character who has been accused in the past of bullying his generals.
Our correspondent says these fresh allegations are likely to cause a political storm and lead to further difficulties for the defence secretary and his team.
The article quotes a former intelligence official as saying the war was now a stalemate.
But Mr Rumsfeld says the US has "no plans for pauses or cease-fires".
[Rumsfeld] thought he knew better
The article says the army is running out of cruise missiles and precision-guided bombs, and that there are maintenance problems with tanks.
"The only hope is that they can hold out until reinforcements arrive," the official told the magazine.
A senior Pentagon planner said Mr Rumsfeld wanted to "do war on the cheap" and thought precision bombing would bring victory.
"He thought he knew better [than military officials]. He was the decision-maker at every turn," the unnamed planner said.
The article says General Franks wanted to delay the invasion until the American troops denied access to Turkey had been brought to Kuwait, but Mr Rumsfeld overruled him.
It says the defence secretary also rejected recommendations to deploy four or more army divisions and to ship hundreds of tanks and other heavy vehicles in advance.
Instead, Mr Rumsfeld preferred to rely on equipment which was already in Kuwait, but was insufficient, the magazine says.
Our correspondent says Mr Rumsfeld and his team desperately need some decisive victories in battle if the American people are to continue to believe what the White House is telling them - that this war is going roughly according to plan.