The US military revealed the latest casualty on Saturday. The marines this month took over responsibility for the region from the 82nd Airborne Division as part of a massive rotation of US forces occupying Iraq.
US army tanks rolled in tight formations through the streets of Baghdad and military helicopters buzzed low over the Tigris river.
These were visible signs of heightened security in the Iraqi capital as the past week had seen a surge in the number of bombings, shootings and mortar attacks on the occupation forces, police and civilians.
It was unclear whether the attacks were timed to overshadow the anniversary of the start of the war.
Situation the same
Iraqis in Baghdad were not sure if much had improved in their lives in the past year despite the fall of Saddam Hussein.
"After one year of liberation, we were looking forward to rebuilding Iraq financially. We hope the country will progress, but the situation is the same as before," said Sabbagh Jaffar.
"The situation on the streets and the economy is the same as a year ago."
Iraqis say US occupation has
failed to bring security
Muhammad Ali added he has had the same job as tea maker for seven years.
"I haven't had a new car or anything, I am still a tea maker. Electricity hasn't improved at all, what has changed? The Americans should leave, it would be better for all of us."
US President George Bush marked the anniversary in a speech at the White House, declaring the fall of Saddam had removed a source of aggression and instability in the Middle East.
"There are still violent thugs and murderers in Iraq, and we're dealing with them," Bush said. "But no one can argue that the Iraqi people would be better off with the thugs and murderers back in the palaces."
Bush's statements, however, fly in the face of reality on the ground, Iraqis say.
"The Americans have failed to provide security and prosperity to the Iraqi people"
Iraqi civilian Ammar Samir
"The security situation is worse than one year ago. I cannot take my family outside at night. When I walk in the street, I do not know when a bomb is going to explode and kill me. We were better secured during Saddam's time," said Ammar Samir, 26, an employee of a private trading company.
"The Americans have failed to provide security and prosperity to the Iraqi people."
Another resident, Saad al-Nuaimi, said the speech was a ploy to attract voters before the November presidential election in which Iraq policy is likely to be high on the agenda.
Al-Nuaimi said Washington had "fabricated lies" claiming Iraq had weapons of mass destruction, although none had been found.
Meanwhile in Mosul, armed fighters fired mortars at the headquarters of the Patriotic Union of Kurdistan (PUK) on Saturday, killing a passerby and wounding three PUK guards and a civilian, police said.
Major Dara al-Surchi, chief of the local police station, said four mortar rounds had been fired. One of them landed in the street outside the PUK headquarters and an Iraqi walking past was killed.
Mosul, 390km north of Baghdad, is an ethnically mixed city - Sunni Arabs make up the largest group, but there is also a significant Kurdish population.
The PUK is one of the two main Kurdish parties. Both parties backed the US-led invasion of Iraq and are represented on Iraq's US-appointed Governing Council.
In Baquba, a US soldier was fatally electrocuted while working on communication equipment at an American base. The incident is under investigation.