Baghdad, Iraq ? Taking a fresh look at postwar Iraq, Defense Secretary Donald H. Rumsfeld met Saturday with senior American commanders and was assured that a recent switch to more aggressive anti-insurgency tactics has begun to pay off.

“It improves — every month it gets better,” Maj. Gen. Raymond Odierno, commander of the Army’s 4th Infantry Division, told Rumsfeld, who nonetheless expressed doubt that the drop in attacks on American troops marked a turning point.

“It’s too early to say it’s a trend,” the defense secretary told reporters after having lunch with soldiers of the 82nd Airborne Division at a muddy outpost on the outskirts of Baghdad.

Security was tight for Rumsfeld’s visit, which was not announced in advance. He arrived and left aboard an Air Force C-17 cargo plane and was whisked from Baghdad International Airport to the 82nd Airborne’s post in a Black Hawk helicopter with gunners aboard.

He also went for the first time to Kirkuk, the center of Iraq’s northern oil fields, and met with L. Paul Bremer, the U.S. civilian administrator of Iraq.

It was Rumsfeld’s second trip to Iraq in four months, reflecting the Bush administration’s push for faster progress toward improving security and speeding the political transition to Iraqi control, as well as an effort by the Pentagon to improve the morale of American troops.

Odierno and other commanders spoke of the more offensive-minded approach to countering the shadowy resistance forces that made November the deadliest month for U.S. forces since the war began in March.

The aggressive tactics, which have included the first use of aerial bombing since the fall of Baghdad in April, have made Iraqis who oppose the resistance less fearful of coming forward with tips on the whereabouts of weapons and fighters, Odierno said.

“When we have a successful operation, other Iraqis come out of the woodwork and offer information,” he said in a briefing for Rumsfeld on recent operations in his area of responsibility. That includes Kirkuk, east to the Iranian border, and a large portion of the area north and west of Baghdad where anti-American sentiment runs highest.

Odierno told Rumsfeld that only about 5 percent of the homemade bombs set by insurgents detonate because U.S. soldiers are getting better at finding them.

The top commander in Iraq, Lt. Gen. Ricardo Sanchez, said in an interview with reporters traveling with Rumsfeld that U.S. intelligence had not established conclusively that fallen Iraqi President Saddam Hussein was directing the insurgency.