Washington ? A week into the war, the optimistic assumptions of the Pentagon’s civilian war planners have yet to be realized, the risks of the campaign are becoming increasingly apparent, and some current and retired military officials are warning that there may be a mismatch between Secretary of Defense Donald Rumsfeld’s strategy and the force he’s sent to carry it out.

The outcome of the war isn’t in doubt: Iraq’s forces are no match for America and its allies. But, so far, defeating them is proving to be harder, and it could prove to be longer and costlier in American and Iraqi lives than the architects of the American war plan expected.

And if weather, Iraqi resistance, chemical weapons or anything else turned things suddenly and unexpectedly sour, the backup force that was expected to be in place in Turkey, the Army’s 4th Infantry Division, is still in Texas, with its equipment sailing around the Arabian peninsula.

Despite the aerial pounding they’ve taken, it’s not clear that Saddam Hussein, his lieutenants or their elite guard are either shocked or awed. Instead of capitulating, some regular Iraqi army units are harassing American supply lines.

“I’m not sure … we gave full credence to the fact that you would have a bunch of bandits riding around in civilian clothes, just wreaking havoc,” Pat Roberts, a Republican from Kansas who heads the Senate Intelligence Committee, said this week of the Iraqi guerrilla fighters resisting U.S. troops.

“This is the ground war that was not going to happen in (Rumsfeld’s) plan,” said a Pentagon official. Because the Pentagon didn’t commit overwhelming force, as it did in the 1991 Gulf War, “now we have three divisions strung out over 300-plus miles and the follow-on division, our reserve, is probably three weeks away from landing.”

Intelligence officials say Rumsfeld, his deputy Paul Wolfowitz and other Pentagon civilians ignored much of the advice of the Central Intelligence Agency and the Defense Intelligence Agency in favor of reports from the Iraqi opposition and from Israeli sources that predicted an immediate uprising against Saddam once the Americans attacked.

The officials said Rumsfeld also made his disdain for the Army’s heavy divisions very clear when he argued about the war plan with Army Gen. Tommy Franks, the allied commander. Franks wanted more and more heavily armed forces, said one senior administration official; Rumsfeld kept pressing for smaller, lighter and more agile ones, with much bigger roles for air power and special forces.

“Our force package is very light,” said a retired senior general. “If things don’t happen exactly as you assumed, you get into a tangle, a mismatch of your strategy and your force. Things like the pockets (of Iraqi resistance) in Basra, Umm Qasr and Nasariyah need to be dealt with forcefully, but we don’t have the forces to do it.”

“The Secretary of Defense cut off the flow of Army units, saying this thing would be over in two days,” said another retired senior general who has followed the evolution of the war plan. “Now we don’t even have a nominal ground force.”

He added ruefully: “As in Operation Anaconda in Afghanistan, we are using concepts and methods that are entirely unproved. If your strategy and assumptions are flawed, there is nothing in the well to draw from.”

“It would have been monumentally helpful for Centcom to have had (the 4th Infantry) division,” retired Lt. Gen. Thomas Rhame said this week., referring to U.S. Central Command, which is directing coalition operations under the direction of Army Gen. Tommy Franks. Rhame commanded the First Infantry Division during Operation Desert Storm.

Franks “should have had the 4th Infantry Division,” Rhame said.

The 4th Division had been slated to open a second front in northern Iraq. That, Rhame said, “would have made Saddam Hussein look in more than one direction. It precludes and prevents him from using his troops in the north in any way in the south.”

A second front did begin to take shape Wednesday, when 1,000 paratroopers landed in northern Iraq. Future airlifts into the area will include tanks and other vehicles, supplies and support personnel, defense officials said.