Winslow Homer’s “The Four-Leaf Clover” suggests a bucolic moment, but that window that can’t be shut and the darkness behind it are ominous. (Courtesy of Detroit Institute of Arts)

The 50th anniversary of the Civil War was all about reconciliation, grizzled old men shaking hands across the wall in Gettysburg, bunking down in tents with the remains of their old regiments, listening to Woodrow Wilson talk of “reunion and hope and patriotic fervor” before heading back to Washington to preside over a more rigidly segregated federal workforce. The second major anniversary — the centennial — was a strained echo of the first, with politicians and civic leaders still nattering on about sectional and racial comity, but it had the air of an awkward family reunion with toxic secrets just under the surface. That was in the early 1960s, with McCarthyism a not-so-distant memory, and the simmering anger of the civil rights movement about to explode.

And what of this most recent anniversary, now that we’ve reached the end of another four-year cycle of remembrance? An African American president held office during the entirety of it, while some sectors of the society celebrated a post-racial America, and others focused anew on the glaring racial and economic inequities of our economic, education and penal systems. We have spent four years, now, thinking about the Civil War, in some ways refighting it and contesting again its legacy and meaning. Have we accomplished anything? Have we made any progress?

If so, it may not be clear for years, not just because it’s difficult to measure how attitudes and understanding change, but also because the anniversary of the Civil War was always an imperfect way to think about the broader currents of 19th-century American history. Anniversaries are a necessary evil of how history is processed in the popular consciousness. They arrive in the arbitrary increments of 10 or 50 or 100 years, with no natural correspondence to larger social forces. Consider an entry in a diary now on view at the Smithsonian’s Anacostia Community Museum. It appears in a family journal begun by Adam Plummer, who was born a slave in Maryland in 1819.

In November 1860, Plummer’s daughter Sarah Miranda was sold to a slave trader and ended up in New Orleans. After the war was over, Plummer and his wife, Emily, sought to reunite with their daughter. They used their savings, and loans and contributions from their extended family, to buy their son Henry a train ticket to New Orleans, where he managed to find his sister, now a widow with a young child. They were reunited with their family in October 1866.

Not quite a half century later, the family journal contains this entry: “Just forty-eight (48 yrs.) years ago tonight Bro. Henry and Sister Miranda returned from New Orleans. October 19, 1914 – October 19, 1866 = 48.”

Sgt. Andrew Chandler of the 44th Mississippi Infantry Regiment, and Silas Chandler, family slave, look like brothers in arms. But what about before and after the war? (Library of Congress Prints and Photographs Division)

It is by our reckoning an irregular interval — 48, not 50 years — marking an event that transpired a year and a half after the war was over. But there’s no reason that the dates inscribed in familial memory should correspond to the dates we remember collectively. Even those who lived through the fighting might have more intense memories associated with events that don’t correspond neatly to the calendars of history: The open-ended wait for a relative who never returned; the ongoing trauma of veterans emotionally shaken and psychically shattered by what they experienced; the grinding poverty of daily life in the South after its economy and infrastructure were destroyed; the disorientation of former slaves grappling with a freedom that was often more de jure than de facto;, the painful readjustment (for men) to civilian life, and the return (for women) to ordinary domesticity.

A recent poem by the Pulitzer Prize-winning poet Yusef Komunyakaa published in the volume “Lines in Long Array: A Civil War Commemoration” dramatizes the irregular ways that private hopes and pain map onto events like the Civil War. “I Am Silas” was inspired by a famous photograph that has been at the center of contentious arguments about the South and slavery to the current day. It shows two young men, one white, the other African American, sitting together, each holding a fearsome-looking knife, with a single rifle lying across both of their laps as if to suggest they are conjoined by its barrel. The white man is Andrew Chandler, a Confederate soldier and son of a slave owner from Mississippi, the black man is Silas, a slave who served his young master during the fighting, including rescuing him from an unnecessary amputation and delivering him to decent medical care after Andrew was wounded at Chickamauga. The poem takes liberty with what is known of Chandler and Silas, imagining a close companionship before the war, and a sense of genuine care and affection during the days after Andrew’s wounding:

“. . . Sometimes,

if you plant a red pear tree

beside an apple, the roots tangle

underneath, & it’s hard to say

Gens. Wesley Merritt, Philip Sheridan, George Crook, James William Forsyth and George Armstrong Custer in the waning days of the war, and before the beginning of their next one. (Library of Congress Prints and Photographs Division)

if you’re eating apple or pear.”

The original photograph has been used to justify the belief that African Americans served happily in the Confederate army, which plays into the resilient myth that slavery was not the root cause of the war, and that slaves were not unhappy with their lot. But Komunyakaa extends the poem to the days and years after the war, to suggest that after Silas saves a man who was his master and perhaps his friend, he is shown no love or consideration once free: “When we came back,” he writes in the voice of Silas, “I was ready to bargain for a corner of land/but history tried to pay me/in infamy . . ./ & a few pieces of tarnished silver.” The poem extends the narrative of slavery and race to the years both before and after the war, capturing an emotional complexity undisclosed by mere historical analysis.

Foremost among all the things not easily accommodated by a historical perspective that prioritizes the war years as its organizing principle is the history and failure of Reconstruction, the great next chapter that arguably played as large a role in the formation of the racial future as the war and emancipation. These two periods, the war and Reconstruction, are chronologically contiguous, but occupy radically different places in the general American consciousness. One is the subject of intense curiosity, extensive remembrance, rampant mythologizing and an industry of book-writing both scholarly and popular; the other is almost entirely terra incognita for most Americans.

A decade ago, when Eric Foner wrote “Forever Free,” an account of Reconstruction for mainstream audiences, he found myriad markers of how absent Reconstruction remains in our national consciousness: At that time, only one National Park Service site out of hundreds was particularly devoted to the events of Reconstruction; tests administered to high school students showed that their ignorance of Reconstruction was greater than any other subject in American history; and a best-selling book that prescribed some 1,000 basic facts everyone should know included not one fact relevant to Reconstruction.

At the National Portrait Gallery, senior historian David Ward doesn’t think that’s changed, which is one reason his next exhibition will treat the Civil War as just one piece of a larger narrative, beginning before and lasting well after the actual war itself. “Dark Fields of the Republic: Alexander Gardner Photographs 1859-1872” deals with a photographer primarily known for having brought the carnage of the battlefield home to a wide American audience, and for being the favorite photographer of Lincoln. But Ward sees the importance of Gardner’s work extending into the age of westward expansion, the confrontation and exploitation of Native American populations, and the emergence of a more ambitious and imperial United States. The Civil War and Reconstruction, he says, were only part of a larger “war over the nature of the union which continues well into the 20th century.”

By expanding the focus from the battlefield to the larger “fields” or landscape of America, the show will push the historical narrative into a period when the federal government begins to take the expansive, nationalized form we know today, an era of railroad building and land-grant colleges, when the prewar promise of “Manifest Destiny” was realized with all the technological and military prowess the government could muster.

One photograph, in particular, stands out for Ward as laden with meaning. It shows five union officers from the Civil War, including Philip Henry Sheridan and George Armstrong Custer, gathered around a table. It was taken in 1865, and might seem a valedictory image by men who had accomplished their mission. But it isn’t.

“These are the guys who fight the Indian wars,” says Ward. “They are all moving west. The war doesn’t stop for them.”

For Native Americans, the end of the Civil War brought only more violence and suffering. For African Americans, the promises and failure of Reconstruction, and the de facto apartheid of Jim Crow made the promise of emancipation often seem desperately shallow.

Even today, the country is still divided, North and South, in ways that people love to parse on social media and in the partisan press: Vast differences in social attitudes to race, sexuality and religion, and significant differences in educational attainment, lifespan, obesity and other markers of well-being. The basic division of Red and Blue America, which has governed our thinking for decades now, map onto more than just the North and South, with rural and urban cleavages as well; but for most of the states that fought the war 150 years ago, today’s red and blue are basically yesterday’s gray and blue.

It’s tempting to say that is the lesson we’ve just learned from the most recent anniversary: The war isn’t over, it was never over, and it continues now by other means. But we’d be wrong to think we have just discovered that truth. In the early years after Appomattox and the assassination of Lincoln, a muted sense of dread haunted the country. Even with the war ended and the country moving on to new endeavors, there was a powerful intuition that the war would not be easily packaged, delimited and contained within neat historical parameters. In 1873, Winslow Homer, who had covered the war as an illustrator for Harpers, painted what at first appears to be a slightly saccharine, sentimental picture of a girl in a white dress, seated among grass and flowers. Homer created some of the most incisive images of the war — a sniper in a tree, a Confederate soldier standing on the ramparts taunting Union soldiers to fire, off-duty troops lost in meditation — but eight years later it seems perhaps he’d moved on to happier subjects.

But no. The painting, titled “The Four-Leaf Clover,” positions the girl in front of a window that is partially open, with a pot of bleeding heart flowers slightly askew beside her. A black ribbon is woven into her hat, and the lay of the ground is strangely angled to one side. The window must lead to a basement, because whatever is behind it is lost in inky darkness. It is a powerfully conflicted picture, a black hole of ominous and disturbing proportions framed in an innocuous image of sweetness and light. It is, of course, the unresolved issues of the war that are being memorialized. The window is open to suggest the lack of closure, its panes are darkened to suggest the trauma just beneath the surface of American life. And the four-leaf clover?

It stands for wishful thinking, the powerful, often unthinking optimism that sweeps all before it, leaves no time for delving into anything painful, anything complex. Like the founders of our country and the problematic constitution they created — which made a moral reckoning with slavery inevitable — the four-leaf clover suggests the folly of trying to wish away the structural problems that grind us down. Some part of America has always been a child, naively hoping for the best.

It is a painting about trauma, the ongoing nature of trauma, the unresolved trauma of the nation’s birth and rebirth, both bathed in blood and in hope. History and trauma share this: Nothing is ever over. If we’ve learned that during the last four years, perhaps we’ve grown up a little. If not, we will be sitting once again before the same window, wishing away the old ugliness of our divided nation, in 2065.

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