Two car bombs in Baghdad killed at least 11 people Sunday, including one American soldier, and Defense Secretary Donald H. Rumsfeld visited U.S. troops and diplomats in the capital and at a remote desert air base.

Rumsfeld, making his first visit to Iraq since May and his sixth overall, held a town hall-style meeting with more than 1,500 U.S. Marines at Al Asad air base in western Iraq. Likening the fight against terrorism to the Cold War, he told the Marines they were participating in a "task for a generation" and stood at "ground zero" in the "struggle against fanaticism, extremism and terrorism."

Rumsfeld said more violence was likely as Iraq moved toward elections that are planned for January. "Those who are determined to take back Iraq, back to a dark place, are trying to derail the new Iraqi government. . . . They're trying to snuff out any signs of progress," Rumsfeld said. "Their goal is to topple moderate governments. The extremists have made Iraq a key campaign in their struggle."

Rumsfeld flew to the air base, the current home of the 3rd Marine Air Wing, early Sunday morning from Manama, Bahrain, then made unannounced flights into northwestern Iraq and on to Baghdad, where he met with Gen. George W. Casey, the most senior U.S. general here, and U.S. Ambassador John Negroponte.

Rumsfeld concluded his day in Iraq by flying to the northern oil center of Kirkuk. Commanders there told Rumsfeld that efforts to integrate the Iraqi National Guard and police into regular security patrols and missions have significantly reduced the number of insurgent attacks and allowed an ethnically diverse city council to begin taking control. The secretary also met with South Korean troops in Irbil before departing Iraq under a rare drizzle and flying to Skopje, Macedonia.

Rumsfeld's travels did not place him in proximity of the bombings in Baghdad. In the first attack, a U.S. soldier was killed when a vehicle detonated near a military convoy in east Baghdad. The second explosion was near the main Iraqi police training academy, where recruits and applicants often gather in large numbers.

Ali Dahaan, 45, said he was stuck in traffic on Palestine Street when a minibus exploded outside the police academy. He said he covered his daughter's eyes each time someone carried a piece of a body past the car.

"I am without hope," the Iraqi businessman said. "I will go to the passport office to get my family passports and leave Iraq. But I don't know what will become of the people who have no money to go. They have to live here and face these explosions."

In the east Baghdad slum of Sadr City, U.S. forces and the militia of Shiite Muslim cleric Moqtada Sadr observed the spirit of an initiative aimed at ending almost daily combat there and bringing a large part of Iraq's insurgency into its nascent political process.

Monday will be the first of five days during which militia members are to surrender their weapons in exchange for cash payments. Iraqi security forces then will be free to search suspect houses. In return, Iraq's interim government will free all Sadr followers not convicted of a criminal or civil offense, said Qasim Daoud, Iraq's national security adviser.

"We are trying to concentrate on the concept of the rule of law, disarming all of the illegal militias and arresting all of the terrorists," Daoud said. "These concepts are paramount in our minds."

In addition to the killing of the soldier in Baghdad, the U.S. military also announced the death of a Marine in Anbar province on Saturday, when a car bomb exploded beside a Marine convoy outside the city of Fallujah.

In his comments to the Marines at Al Asad air base, Rumsfeld said that the days ahead could bring increased activity by insurgents but that "victory ultimately only comes to those who are resolute and steadfast."

Rumsfeld said, however, that 14 of Iraq's 18 provinces are seeing fewer attacks and that as more Iraqi security forces are trained and armed, the situation will steadily improve. "I don't want to be accused of saying it's a rosy picture out here," he said. "It's tough work."

So far, about 100,000 Iraqis have been trained, equipped and readied to serve in the country's security forces, and U.S. officials hope that number will rise to about 145,000 by the end of January. A senior military officer told reporters Sunday that there should be 27 Iraqi battalions by then, the equivalent of three divisions.

Rumsfeld said he had no specific plans to boost U.S. troop levels in Iraq before the elections but that such decisions would depend on whether his generals ask for more help. Casey said he will ask for more troops if he needs them. Rumsfeld also said he could go to coalition partners for more help but expects Iraqi forces to be sufficient.

"This is their country," Rumsfeld said. "It is Iraqis who will have to build this country, it is Iraqis who will have to defend this country."

In Kirkuk, Rumsfeld delivered the same message to Iraqis, saying: "Sovereignty without the ability to protect it isn't sovereignty. What you're doing is to ensure the sovereignty of this country. We can help, but we can't do it. You have to do it."

In Baghdad, Ryiadh Abu Arshad, who watched the aftermath of one of Sunday's bombings while munching a sandwich at a food stand, dismissed the Americans' plans as "100 percent wrong."

"No police in the world are able to stop any terrorism," he asserted. "You need a strong army, and since the American army, the best in the world, couldn't stop it, nobody will. So let's accept it as part of our life. Maybe in the next minute, you and me will die here by the next rocket or car bomb. Who knows?

"Let me finish my sandwich so at least I will die not hungry."

Correspondents Karl Vick and Steve Fainaru contributed to this report.

Medics lift the body of a victim of a car bombing in central Baghdad. In a separate incident, a U.S. soldier was killed when a vehicle exploded in east Baghdad. Defense Secretary Donald H. Rumsfeld talks with South Korean soldiers in Irbil, Iraq. He also met with U.S. troops at Al Asad air base in western Iraq.