On a trip shrouded in secrecy, President Barack Obama flew into Iraq on Tuesday for a brief look at a war he opposed as a candidate and now vows to end as commander in chief.

Obama flew into the country hours after a car b**** exploded in a Shiite neighborhood of the capital city, a deadly reminder of the violence that has claimed the lives at least 4,266 members of the U.S. military and thousands more Iraqis since March 2003.

The visit came at the conclusion of a long overseas trip that included economic and NATO summits in Europe and two days in Turkey.

Shortly before leaving Turkey, the president held out Iraq as an example of the change he seeks in policies inherited from former President George W. Bush.

Moving the ship of state takes time, he told a group of students in Istanbul. He noted his long-standing opposition to the war, yet said, Now that were there, the U.S. troop withdrawal has to be done in a careful enough way that we dont see a collapse into violence.

In office only 11 weeks, Obama has already announced plans to withdraw most U.S. c****at troops on a 19-month timetable. The drawdown is to begin slowly, so American forces can provide security for Iraqi elections, then accelerate in 2010. As many as 50,000 troops are expected to remain in the country at the end of the 19 months to perform counterterrorism duties.

Tuesdays trip was Obamas third to Iraq, and his first since taking office. He met with U.S. commanders and troops last summer while seeking the presidency.

Because of security concerns, the White House made no advance announcement of the visit, and released no details for his activities on the ground.

It was the last stop of an eight-day trip to Europe and Turkey during which Obama sought to place his stamp on U.S. foreign policy after eight years of the Bush administration.

He and other world leaders pledged cooperation to c****at a global recession, and he appealed with limited success for additional assistance in Afghanistan, a war he has vowed to intensify. The new president drew large crowds as he offered repeated assurances that the United States would not seek to dictate to other countries.

I am personally committed to a new chapter of American engagement. We cant afford to talk past one another, to focus only on our differences, or to let the walls of mistrust go up around us. Obama said before leaving Turkey. The visit to a nation that straddles Europe and Asia was designed to signal a new era. He had pledged as a candidate to visit a majority-Muslim nation in his first 100 days in office.

The president flew into Baghdad, and was spending his day at Camp Victory, where he arranged to speak to some of the 140,000 U.S. troops stationed in the country. He was awarding medals to several.

Plans to travel to the Green Zone the heavily fortified U.S. nerve center in Baghdad were scrapped because of bad weather.

Instead, officials said the president would speak by phone with Iraqi Prime Minister Nouri al-Maliki and President Jalal Talabani.

While U.S. casualties are down sharply from the wars height, there were constant reminders of violence. A half-dozen b****s rocked Shiite neighborhoods on Monday, killing 37 people. There was no immediate death toll available from the car b**** incident that occurred a few hours before the president arrived on Tuesday.

The military is in the process of thinning out its presence ahead of a June 30 deadline, under a U.S.-Iraq agreement negotiated last year that requires all American c****at troops to leave Iraqs cities. As that process moves forward, the increase in b****ings and other incidents is creating concern that extremists may be regrouping.

There was no indication Obama planned to visit Afghanistan before flying home to Washington aboard Air Force One, although he has emphasized the importance of that war over Iraq

Little more than a week ago, the president announced a revamped Afghanistan strategy that calls for adding 21,000 troops, narrowing the focus from nation-building to stamping out the Taliban and al-Qaida and broadening the mission to include pressure on Pakistan to root out terrorist camps in its lawless regions.

Afghanistan was a big topic of conversation with fellow world leaders on the earlier portion of Obamas trip, particularly the part that took him to a NATO summit in Strasbourg, France.

Obamas opposition to the Iraq war helped him enormously in his campaign for the presidency. It helped him defeat former rival now Secretary of State Hillary Rodham Clinton in the Iowa caucuses that were the first test of the race, and aided his campaign against Republican Sen. John McCain last fall.

The end-the-war plan Obama announced in February was aimed at fulfilling his campaign promise to end c****at in Iraq within 16 months of taking office. Contrary to hopes among some Democrats and gra**-roots supporters, the plan calls for a 19-month timetable instead.