The American war in Iraq is over. The last U.S. soldier will be home by Christmas, and for the first time in a decade, no American service member is preparing for deployment in Mesopotamia.

As America leaves the Iraq war, what has the war left America?

There are the images.

Where Vietnam gave us the Huey helicopter landing among rotor-washed palms, Iraq’s icon is the Humvee rumbling through a dun-colored landscape of desert. The arc of the American experience in Iraq can be told through the collage from hope to barbarity, from swaggering invasion to quiet departure.

Those pictures capture
the early celebration-by-defacement — the ebullient tearing down of the murals, statues and mosaics of Saddam Hussein, at times aided by U.S. troops pleased that the initial thunder run to Baghdad had ended swiftly.

But the joy passed quickly, subsumed by the wholesale looting of the capital and the beheadings of those captured during a nascent insurgency, by the Shiite uprisings and the Sunni Triangle, by the haunting evidence of American-supervised humiliation and torture inside Abu Ghraib, and by the bodies of Blackwater contractors hanging burned and beaten from a steel bridge over the Euphrates.

Beyond the images, the war has left a legacy of lasting effect on American politics and culture. There is the federal debt, inflated by an estimated trillion dollars spent on the war, along with more than 4,400 dead troops, a generation of young amputees, a fragile ally in the heart of the Arab Middle East and narrowed ambitions for American power.

“History will judge the decision to go into Iraq,” President Obama said this week , then listed the achievements secured by the more than 1 million American troops and civilians who have served there since March 2003.

Those gains — an emerging democracy in an oil-rich Arab nation, freedom for millions of Iraqis from a dictator’s brutal whimsy — remain vulnerable in a heavily armed country with a light rule of law. But Obama will celebrate them Wednesday when he travels to Fort Bragg in North Carolina to spend time with some of the troops and military families who bore the brunt of the nearly nine-year war.

A contested premise

The second front of George W. Bush’s “war on terror” was never the popular one.

The premise was contested from the start, a new doctrine of preemptive war tailored to an era in which stateless militants could batter the once-distant United States with the everyday tools of modern society — commercial jets as missiles, cellphones as triggers, trucks as bombs.

The neoconservatives at the Pentagon and in the West Wing argued that the invasion of Iraq was necessary. Hussein, the longtime U.S. nemesis who once tried to kill then-President Bush’s father, was openly encouraging Palestinian militancy at a time when Hamas was blowing up cafes and pizzerias in Jerusalem. A model of democracy in the Middle East — imposed by the U.S. military — would inspire change in its neighbors or frighten them into reform.

Besides, Hussein had murdered hundreds of thousands of his own people in the Anfal campaign against the Kurds, and in the aftermath of the 1991 Persian Gulf War to put down a Shiite rebellion that the United States failed to support after pledging to do so — a broken promise that helped fill the mass graves of Hilla, south of Baghdad. And he supposedly had an arsenal of some of the world’s nastiest weapons that had to be found and destroyed before they ended up with al-Qaeda.

Even some liberals felt hawkish about Hussein. Others, including then-state Sen. Barack Obama of Illinois, opposed the military action on the grounds that it was a distraction from the more important war against al-Qaeda. He called it “dumb,” and years later, his opposition proved key to his winning an against-the-odds fight for the Democratic presidential nomination.

The left-of-center doubts dissipated quickly in the “shock and awe,” as Defense Secretary Donald H. Rumsfeld described it, of the pre-dawn bombing of Baghdad in the last weeks of March 2003.

Along the Tigris River, the hulking ministries of Hussein’s rule were set ablaze by American munitions. Over the berm separating Kuwait from Iraq plunged the 3rd Infantry Division, the 1st Marine Division, the 101st Airborne Division and other units in a sprint for the capital.

On May 1, 2003, Bush declared that “in the battle of Iraq, the United States and our allies have prevailed,” a “Mission Accomplished” banner serving as his backdrop on the deck of the U.S.S. Abraham Lincoln.

Looters had by then decimated the wealth of Baghdad’s terrified middle class and absconded with much of the country’s ancient cultural heritage. The chaos also had sabotaged the slim faith Iraqis had in the American project to bring a new form of government to a nation traumatized by decades of dictatorship. U.S. troops watched the turmoil unfold, uncertain of their orders.

Cascading violence

By then, American hubris was already being implicated in the lack of U.S. planning and the failure to anticipate the backlash of Iraqis. The promised shower of sweets that was supposed to have greeted the American liberators never materialized.

In the trash-strewn streets of Baghdad’s Sadr City, plagued by flickering electricity and unmet American promises, U.S. troops rained soccer balls and lollipops down on the ragtag children escorting their Humvees. As the photos of hooded Iraqi prisoners emerged from Abu Ghraib and Moqtada al-Sadr’s sectarian militia rose up across southern Iraq, the kids started throwing the goodwill gifts back, aiming the hard candy at the soldiers in their gun turrets.

A few months later, U.S. forces would fight the most intense urban battle since Vietnam in the streets of Fallujah.

The violence cascaded over the country and turned Baghdad into a killing field. More than 140,000 U.S. troops were unable to keep Iraqis from killing each other, and Bush, watching his gamble to build an Arab democracy fall into civil war, doubled down in January 2007 by announcing a surge of what would end up being an additional 30,000 troops.

The new troops lived in Iraq’s most violent neighborhoods. Sadr called a cease-fire, yanking his Shiite militia off the streets, and a U.S. effort to purchase the loyalty of the Sunni leadership in volatile Anbar province succeeded.

Violence decreased, and a form of sectarian politics emerged, slowly. Elections brought in new leaders and power-sharing; parliamentary maneuvering took the place of running gun battles and midnight kidnappings. The progress was halting, accompanied by violence. But exhausted by conflict and terrorism, Iraqis began to govern themselves.

It’s less clear what will happen now that America’s military is leaving. A stronger Iraqi security force has been left behind, along with the architecture of the U.S. war and occupation represented by the blast walls and razor wire still crisscrossing the capital.

Yet many of the problems — from the future of the Kurdish north to the sharing of Iraq’s vast oil wealth — remain unresolved. What is clear now is that the problems are for Iraqis to fix, not a U.S. battalion commander.

A changed approach

Iraq, like Vietnam before it, has shadowed the current administration’s approach to the world.

The vocabulary has changed along with the policies, signaled early by Obama in his Cairo address to the Muslim world in June 2009, when he declared, “Let me be clear: No system of government can or should be imposed upon one nation by any other.”

Last spring, Obama weighed whether to intervene in Libya’s uprising against Moammar Gaddafi, a dictator as notorious in the annals of American history as Iraq’s Hussein.

There was no talk of “shock and awe,” only the “unique capabilities” that the United States could bring to the rebellion (namely, aerial bombardment and intelligence). There was no declaration of “Mission Accomplished,” and barely a declaration of a mission at all, as Obama argued with Congress that no war powers authorization was needed because U.S. troops were not serving in harm’s way in Libya.

Instead, Obama outlined a set of parameters to justify the intervention and tacitly contrasted those with the decision to invade Iraq. Only when the civilian population faced an imminent threat of massacre, and only with broad international support that included U.N. approval and military participation from allies, did the United States head into war.

In announcing two months ago the impending withdrawal of all troops from Iraq, Obama noted that “this December will be a time to reflect on all that we’ve been through in this war.”

Then he began his own reflection, shifting the country’s focus from Iraq to a troubled domestic economy that he called “the greatest challenge that we now face as a nation.” He called on the veterans of Iraq to help.

“Because after a decade of war, the nation that we need to build — and the nation that we will build — is our own,” he said.