Start delving into Civil War history and you quickly find out just how contested the memory of the war is.
Historian Gary Gallagher of the University of Virginia likes to take people to historical sites to untangle the threads.
“The three main memories that came first were Union, Emancipation, and Lost Cause. That's the majority white northern memory, the African American abolitionist memory and the white southern/confederate memory. Those all come immediately. Reconciliation really gains steam as you get closer to the end of the 20th century," Gallagher says.
Gallagher is giving a group of school teachers a tour of civil war memorials in Charlottesville, Virginia. He stops in front of a towering statue of Robert E. Lee on horseback and marvels at how well Lee's reputation has fared. Gallagher says the confederate general ended up on no less than five US postage stamps.
“How weird is that? How many civil wars decide later to put the people who almost ruined the nation on a postage stamp," he says.
Here's what happened in April 1865.
The Union General Ulysses S. Grant had finally encircled Lee's Army of northern Virginia near Richmond. Lee gave up the Confederate capital and began a rapid retreat. At a critical moment rail cars that were supposed to contain food for Lee's starving troops turned out to hold ammunition but no food. The retreat turned into a death march. Lee soon found himself surrounded on three sides. Events reached their climax at Appomattox.
The site is now a National Historical Park and Gallagher knows it well.
"You get a great view across the river from here toward the fields beyond where the army of northern Virginian bivouacked on the last night. They talked that night about whether the army should be surrendered. Grant had already sent notes to Lee proposing surrender. Lee didn't think it was time to surrender yet," he says.
Lee still hoped to punch through Grant's lines the following morning. He ordered some of his men out on what turned out to be a hopeless mission.
"These are guys who are going to be killed to absolutely no purpose on the morning of April the 9th," Gallagher says.
Lee finally decides to surrender. The historic meeting between Grant and Lee follows that afternoon.
"Welcome to the McLean House. This is where the surrender of the Army of Northern Virginia took place, specifically in this room that's over on the left when you go in. It's called the parlor room," the park ranger tells us.
The surrender marks the beginning of a much-loved story about reconciliation between north and south.
Jay Winik, who wrote a recent bestseller about the end of the war called "April 1865: The Month That Saved America," says what happened that day at Appomattox was critical. Winik says Grant's attitude was key.
"He decides to allow the South to keep their sidearms and to keep their horses. Now of course that made no sense if you're worried about guerrilla war taking place. But what Grant was saying, quite loudly and forcefully, is 'We may have defeated you, but we honor you. We may have defeated you, but you are to become our brothers again," Winik says.
Grant was carrying out the wishes of the president, Abraham Lincoln. Winik says Lincoln believed it was essential the end of the war not be bitter or bloody.
"What was so striking about him is he never hated or demonized the enemy. You know, he would look across the Potomac and he would stretch an arm out and say, 'You know if only those people had behaved over there, we wouldn't be in this terrible war.' He didn't call them 'the enemy,' he called them 'those people'," Winik says.
Lincoln saw ‘those people’ as fellow citizens, fellow Americans.
But just five days after Appomattox, Lincoln was assassinated. It was a terrifying moment. Lee had surrendered his army but there were other confederate forces in the field, still poised to fight.
Winik says no one knew what would happen next.
"It was sort of like their 9/11 of the day," he says. "People literally feared being murdered in their beds and seeing their cities being torched. If ever there were a time for the South to be poised to take advantage of the chaos rippling through the union, it would have been then. But quite significantly, when a number of confederates came to Lee, who at this point was back home in Richmond, and talked about the possibility of guerrilla war, very decisively and decidedly, Lee said no to guerrilla war saying 'It must not be fought, it probably couldn't be won, and we should not wage it under any circumstances."
Winik places huge emphasis on Lee's decision to say no to guerrilla war and yes to re-joining the union.
"Had Robert E. Lee, at the end of the Civil War, instead of doing what he did at Appomattox, had he, with simply just a wink and nod said yes to guerrilla warfare we would be living in a country today and the war never would have ended," he says.
In Winik's version of the Civil War that ending was definitive. Not only that, it would prove triumphant for the future of the country.
Back at present-day Appomattox, a storm has arrived.
Gallagher ducks into the old jail building to get out of the rain. He says Appomattox was the start of reconciliation, but not the end of it.
"I think one thing we get wrong is thinking that this had really just after all been a family quarrel where people were upset with each other, but fundamentally not really at odds with one another and that it was easy to put humpty back together again, but I think there were tremendous divisions and levels of bitterness," Gallagher says.
That bitterness and the political violence it unleashed leads some to conclude that the civil war didn't really end in 1865.
Political scientist Stephen Biddle sees war not just as a series of military battles but as a violent contest for competing political outcomes.
He says a big part of the war was about race and rights--with the North trying to impose its view of the political rights of southern blacks on the South.
"So you get an end of nominal active hostilities in 1865. The North then essentially occupies the South militarily, in an attempt to enforce its political preferences for the rights of southern blacks. The South, by contrast with the standard grade school narrative, doesn't accept this. They keep fighting," he says.
Like the insurgents in Iraq who weren't happy with the political outcome of the US - led invasion in 2003. Biddle says the Confederates found a way to continue the war.
"It's just they don't keep fighting in serried ranks of grey, in big battles with large formations, what they end up doing is they fight a guerrilla war," Biddle says.
It's not the same as the guerrilla war that Lee rejected in April 1865, but Biddle and others argue that it is guerrilla war nonetheless. It's fought by a variety of militia groups including the Ku Klux Klan. Much of the resistance was directed at the federal government's attempt to enforce black voting rights in the south in the period known as Reconstruction.
In Louisiana for instance, African-Americans enjoyed strong federal protection in the elections of 1868, 1870 and 1872, according to historian Lee Anna Keith.
"In all three of these elections black voter participation is near 100%. The army, acting as army of registrars, sweeps into black communities, and they sign up every eligible man and these men turn out on election day in force," Keith says.
But the backlash was fierce. Thousands of blacks were killed during Reconstruction.
In her book The Colfax Massacre Keith writes about an incident in Louisiana in 1873 where contested election results led to a pitched battle between hundreds of white Democrats and black Republicans.
The blacks had camped out in the courthouse to prevent the other side from installing their candidates. The whites invaded, firing a cannon and forcing a black prisoner to set fire to the roof. When the blacks inside the courthouse tried to surrender they were slaughtered.
"In the aftermath, army troops swooped in to investigate the killings. The perpetrators fled. And their sympathizers refused to cooperate," she says. "By resisting the army, threatening and intimidating them, spitting tobacco in the face of army officers, all this stuff happens in the aftermath of Colfax. And so there is a strong sense that the war continues, and that the Confederacy has not been defeated, because local people are thwarting the aims of the US military in the region."
In the end three of the killers were prosecuted and convicted, but the Supreme Court threw out the convictions, paving the way for violence to triumph over voting rights throughout the South.
Colfax and other incidents like it effectively ended Reconstruction. In fact a historical plaque at Colfax gloats that the event "marked the end of carpetbag misrule in the south."
Historian Ed Ayers likens the end of Reconstruction to the departure of the United States from Vietnam.
"I can remember what it felt like to see the video of the last helicopter leaving Saigon and people clinging to the runners of the helicopter. Reconstruction was like that, you know, except that there were millions of African Americans clinging to the helicopter of Reconstruction. It was never actually completed. It was just abandoned," Ayers says.
Ayers thinks the messy struggle that followed the war is one reason Americans cling to the story of Appomattox. He says the gentlemanly handshake between two great generals gives us the illusion of a clean ending.
"We just love that story, not thinking about days after that Abraham Lincoln's assassinated, two years after that military reconstruction begins, a decade after that Reconstruction finally comes to an end. Americans are most uncomfortable with the period of Reconstruction of anything else in our history, because it's not a story, it doesn't have any kind of shape to it, it just kind of explodes," he says.
After the invasion of Iraq, Ayers was dismayed that in all the public debate over post-war reconstruction in 21st century Iraq, no one bothered to look at post-war reconstruction in the 19th century American South. After all, it involved many of the same elements: military occupation, democracy-building and economic development.
But administration officials and pundits alike ignored it.
"They said well, look how quickly we reconstructed Japan after World War Two and look how we reconstructed Germany, that's what we have in mind for Iraq. I said, what if we looked at our own reconstruction which generally is considered a failure," he says.
It's helpful to look at Iraq through the prism of the Civil War and the Civil War through the prism of Iraq.
Biddle says it helps him understand how it's possible to win the war, capture the capital, but still lose the peace. He notes the North won the big military contest between 1861 and 1865. But that didn't end the struggle. And over time, Biddle points out, Southern resistance paid off. In 1877, President Rutherford Hayes withdrew Northern troops from the South.
"And the South then proceeds to essentially run out the Northern-installed governments of the remaining Southern states, institute what amounted to white one-party rule, remove blacks from voters rolls throughout the South and establish a system of segregation. And that system remains to a significant degree all the way up until the civil rights movement of the 1960s," he says.
Biddle says if you look at the war in political terms it's possible to construct an argument that the South actually won the war.
Ayers doesn't go that far, but he certainly agrees with Biddle that you have to take the long view to understand what was at stake.
"How really just raggedly brutal the war was, how uncertainly it came to be about slavery, how tenaciously the white South fought for generations to erase as much as they could of what the war had decided. So if you think of the war as being something other than just the battles on the battlefields but what caused it, what it was for, what its consequences were, then it took a very long time for the Civil War to come to anything like an end," he says.
And the same could well be true in Iraq, where a complicated and still violent struggle for power continues.