STATE DEPARTMENT — President Barack Obama's withdrawal of most troops from Iraq and the scaling-down of U.S. diplomats in Baghdad closes the defining foreign policy campaign of his predecessor, President George W. Bush.
A decade after the invasion, which began March 19, 2003, analysts debate what the United States got out of the war in Iraq.
Ten years after President Bush sent troops to Iraq, Washington appears to have little influence over what goes on there.
Shi'ite Prime Minister Nouri al-Maliki continues to dominate Sunni opponents with what Johns Hopkins University professor Ruth Wedgwood says are few repercussions.
"There really is nobody for them to worry about. And Maliki seems quite content to have a perpetually unsettled Iraq in which the Sunni will sooner or later find their means to take revenge, but for the moment it is a Shia nation," she said.
With the U.S. handover, Wedgwood says Prime Minister Maliki is free to do as he likes.
"I think when we withdrew so completely, albeit leaving behind this carapace of an empty embassy behind, it really was taken by Maliki as a kind of 'do as you wish' signal," she said.
Especially in Baghdad's pursuit of better relations with neighboring Iran.
"Maliki I think has always been under the sway of the mullahs in Iran. He has made no secret of that. And he has more or less gotten away with it," said Wedgwood.
That's a problem for the Obama administration in enforcing sanctions against Iran's nuclear program, and in Syria, where Iran is backing embattled President Bashar al-Assad.
U.S. Institute of Peace analyst Steve Heydemann says Baghdad is taking sides in Syria against the United States.
"They have been permitting over-flights from Iran, which the U.S. would like them to stop," he said. "They have been providing other kinds of support to the Assad regime and have turned something of a blind eye as Iraqi Shia - who are moving into Syria to support the regime - are crossing the Iraqi-Syrian border."
Heydemann says Syria's war risks further undermining Iraq.
"It is sharpening sectarian divisions within those neighboring countries in ways that could have very, very troubling consequences for stability in those countries. And I think Iraq is one of the countries most at risk of instability as a result of the Syrian conflict," he said.
U.S. firms have profited from the privatization of most Iraqi oil. But even there, divisions persist between the government in Baghdad and semi-autonomous Kurdish leaders in the north.