Rumsfeld waited too long to reroute the 4th Infantry Division's equipment because he believed that precision airstrikes "could do the trick" in bringing down Hussein, one Pentagon source said, speaking on condition of anonymity.
"The Army is feeling hamstrung" by the Office of Secretary of Defense, he added.
Such views are not shared by senior U.S. commanders, nor at this point by some Army officers who have questioned Rumsfeld's decisions in the past.
At Central Command headquarters in Doha, Qatar, officials said attacks on the supply line had been expected and were being dealt with as expeditiously as possible, given the coalition's concern with avoiding civilian casualties.
"And these [attacks] are ones and twos, and that you're going to live with, like we live with in Afghanistan," Rumsfeld said at Tuesday's Pentagon briefing.
Inside the Army, where Rumsfeld's views on light and heavy forces have most often been challenged, a ranking officer positioned to monitor developments in Iraq said of the recent challenges:
"In the whole scheme of things, they are not a big deal."
The lack of a second front in northern Iraq has had no real impact on resistance in the south, he said, because there has been no measurable shift of resources from north to south. The coalition's air supremacy and other resources have made such movements too risky for Iraq to attempt.
Moreover, the paramilitary fighters mounting attacks along the main supply route north from Kuwait were dispatched from Baghdad, not northern Iraq.
He said he had seen no reports of units running low on fuel, ammunition or other vital supplies during their advance. The absence of such problems indicates that the problems in southern Iraq have so far had little impact on the overall attack, the officer said.
The Iraqi resistance in southern Iraq "hasn't prevented us from doing anything, but it has made it more difficult," said Jeffrey White, a military analyst at the Washington Institute.
"Their approach has been to fight where they could," he said, given the limits on Iraq's ability to maneuver on terrain dominated by coalition air power. He said helicopters and rapid response units from the 101st Airborne could take on the task of guarding supply convoys.