I’ve been writing books for 25 years now—I’m sure that silver anniversary festschrift is just around the corner—and I never reply to critics. I’ve had my say between the covers; let the reviewer have her say. Besides, life is too short and precious for squabbling with strangers. But Sidney Blumenthal’s claim in the Atlantic that Ron Maxwell’s film “Copperhead,” for which I wrote the screenplay, is “propaganda for an old variation of the neo-Confederate Lost Cause myth” is nonsense. (As recently as 2005 the Atlantic’s erstwhile literary editor, the great Benjamin Schwarz, was recommending my work to readers. Time doth fly.)

Mr. Blumenthal is so busy burning strawmen that he misses the point of the movie (and even misreports the ending, which he must not have seen). “Copperhead” does not re-argue the Civil War, nor is it about the antiwar movement in the North. It measures the impact of the war on the Corners, one small settlement in Upstate New York. Abner Beech, the title character, does not even consider himself a Copperhead; he is, rather, an old-fashioned Jefferson-Jackson agrarian Upstate New York Democrat. (In contrast with the Democratic Party in New York City, the Upstate Democracy contained a large and noble faction that had long sought to bar slavery from the territories and limit the power of the slavocracy.)

The movie is about the effect of war on a community. It is about the way that wars tear families apart. It is about the challenge of loving one’s neighbor. And it is about dissent, which is never exactly in robust condition in the land of the free.

“Copperhead” is based on a novella by Harold Frederic, who is not quite as obscure as Blumenthal believes him to be.

Harold Frederic, born in 1856, was a native of Utica, which though it is but the eighth largest city in New York can fairly stake a claim to being, pound for pound, the literary capital of the state. Frederic lived a short but full—perhaps overly full—life. In brief, he began his career as a Utica and later Albany newspaper editor, in which capacity he was celebrated as a wit and bon vivant. He was a good friend of fellow Upstater and U.S. President Grover Cleveland, whose Jeffersonian Democratic political convictions Frederic shared. He left his native grounds—for good—in 1884 to become a New York Times foreign correspondent based in London. Between 1886 and his death in 1898, he published more than a dozen books, most famously The Damnation of Theron Ware (1896), a tale of a simple Upstate Methodist minister’s loss of faith which is widely considered a masterpiece of late-19th century American realism. (F. Scott Fitzgerald called The Damnation of Theron Ware “the best American novel” written before 1920—the same year, coincidentally, that This Side of Paradise was published.)

The Copperhead—its title taken from the derisive serpentine epithet applied to Northern critics of the Civil War—was serialized in Scribner’s Magazine in 1893 and published in book form that same year. The novel, or novella, or longish short story, as you prefer, would reappear in several collections of Frederic’s fiction, most notably in The Civil War Stories of Harold Frederic, under the imprint of Syracuse University Press and with an introduction by Edmund Wilson.

In every incarnation it sold poorly, as Frederic’s work usually did. But then The Copperhead, as with his other stories of the Civil War, hit none of the expected notes. It catered neither to “Battle Hymn of the Republic” Northern righteousness nor “Dixie” Southern romanticism.

Edmund Wilson, our greatest literary critic and a denizen of that magical literary ground surrounding Frederic’s Utica, wrote that Frederic’s “stories of New York during the Civil War reflect the peculiar mixture of patriotism and disaffection which was characteristic of that region… Due to this, these stories differ fundamentally from any other Civil War fiction I know, and they have thus a unique historical as well as a literary importance.”

There is an unblinking, unsentimental honesty to The Copperhead, as well as Frederic’s other stories of the war. The fanfare and spangles, the soaring rhetoric and battlefield heroism: you’ll find none of that on his York State homefronts. We are shown, instead, a little world pockmarked, drained of life, even, by what—and who—is absent. Young men leave communities of which they are essential pieces. Some return intact but irreparably altered; some stagger home shattered; others make the trip back in pine boxes. The normal rhythms of courtship are disrupted. The interdependence of small farms, crossroads shops, and little Protestant churches is unraveled, and we are given to understand that things will never be the same.

Stephen Crane, whose own The Red Badge of Courage is commonly regarded as the great American Civil War novel, said of Frederic’s Civil War tales that they illumed “the great country back of the line of fight—the waiting women, the lightless windows, the tables set for three instead of five.” This was the side of war that is most immediate for Americans yet which seldom interests our artists, let alone our politicians: The war at home. The domestic consequences of our crusades.

Frederic said that he based his Civil War stories on “my own recollections of the dreadful time—the actual things that a boy from five to nine saw and heard about him, while his own relatives were being killed, and his school-fellows orphaned, and women of his neighborhood forced into mourning and despair—and they had a right to be recorded”—however inconvenient these memories may be.

Typically, in a story of a dissenter, the author flatters himself and the audience. The deck is stacked; the cards are marked. Every right-thinking reader or viewer is confident that of course he or she would be at the side of this poor recusant who is being persecuted by narrow-minded peasants or by clerics who deny that the earth revolves ‘round the sun or that man is a product of evolution or that the earth is older than six thousand years or that witches should not be hanged. But really: is there anything easier than standing—at a very safe distance of years—with Galileo or Scopes or the martyrs of Salem?

Harold Frederic does not let the reader bask in his own sanctimony. It’s so easy to say that you’re for free speech; that you honor the First Amendment; that though you may not agree with so and so who says such and such, you’ll defend to the death his right to say it. Well, here’s Abner Beech, an Upstate New York farmer of 1862. He thinks this war between the states—this hallowed war, this bloodletting out of which modern America was born—is an unconstitutional atrocity. He despises the soon-to-be martyred Abraham Lincoln, who by most 21st^t-century lights is the greatest American hero. Abner stands up and speaks his piece—his peace—during time of war.

Okay, Mr. Free Speech. Are you willing to defy the mob and defend Abner?

It’s not so easy.

“Copperhead” is a subversive film. Its subverts narrative convention: Jee Hagadorn, the abolitionist who is absolutely right about the central question of the age, slavery, is a God-is-on-our-side zealot who has transformed a political/moral cause into an abstraction, thereby losing sight of those things nighest unto him—that never happens in real life, huh? The film’s concerns—peace, community, rural Christianity, dissent—could hardly be more relevant in our age of placelessness, perpetual war, and the surveillance state.

In “Copperhead,” the abolitionist Esther (who with her pacifist brother is the moral center of the movie) suggests to the Irish farmhand and Copperhead Hurley that maybe poetry is more important than politics. I believe that; Jee and Abner, the abolitionist and the antiwar Democrat antagonists, do not.

Jee is of course right about slavery. If that were the only issue it’d be a pretty clear case of right and wrong. But that’s not the only issue. From Abner’s point of view, there’s also the U.S. Constitution, which is being stretched and violated by things like the suspension of habeas corpus, the closing down of antiwar newspapers, and, ultimately, the draft, which many Democrats saw, ironically, as a form of slavery. And there’s also the not-so-small matter—which is, bizarrely, often an afterthought—of 700,000 dead Americans. Millions of mothers and fathers, brothers and sisters, wives and girlfriends, have their lives shattered. The communities of which these young men are members are broken apart. From our distance of 150 years we accept this with equanimity; you can’t make an omelet without breaking a few eggs, and they’d have died of something eventually anyway. But I find the enormous death toll a real obstacle to viewing this war as something glorious and wonderful. (Many of the slain were uneducated rural men and thus beneath the notice of moderns, but still, seven hundred thousand?)

I was born in (and repatriated to) the cradle of abolitionism, the Burned-Over District of Upstate New York. The Liberty Party was born a few miles down the road from me. My heroes include the abolitionists of the 1830s-‘50s, brave men and women whose strategies of moral suasion and the passage of Personal Liberty Laws (defiance of the Fugitive Slave Acts) promoted the peaceful abolition of slavery. The great moral and political failure of American history is our failure to have freed the slaves not only many decades earlier but without bloodshed.

Yet if these early abolitionists are my ancestors, so are the antiwar Democrats, who upheld the Bill of Rights against Republican assaults, and so are the old Whigs who tried desperately to keep the union together. Like Whitman, we contain multitudes: Frederick Douglass and Robert E. Lee, Gerrit Smith and Horatio Seymour and Harriet Beecher Stowe… as an American, how are all these men and women not a part of me? Of us?

I write every day with a photo of Eugene V. Debs tacked to the wall on my left. Debs, the leading American socialist of the early 20th century and, more importantly, a faithful citizen of Terre Haute, Indiana, was America’s most famous martyr to wartime speech. In the photo, Debs is addressing an audience in Canton, Ohio, in June 1918, condemning U.S. entry into the First World War and remarking, with wry prescience, that “it is extremely dangerous to exercise the constitutional right of free speech in a country fighting to make democracy safe in the world.”

For this speech, Debs became one of 15,000 Americans jailed for violating President Woodrow Wilson’s Espionage and Sedition Acts. As Judge Kenesaw Mountain Landis explained when handing down a twenty-year sentence in another such case, “In times of peace, you have a legal right to oppose, by free speech, preparations for war. But when war is declared, that right ceases.” Strange, isn’t it, how the Founders never got around to appending that footnote to the First Amendment?

Copperhead critics of the Civil War were often persecuted, too, though certainly not to the extent that dissenters from the First World War were. Newspapers were shut down, antiwar editors and speakers were imprisoned, habeas corpus took a holiday. War is always the enemy of liberty and free speech.

Those who wish to investigate the Copperheads further should read the works of the late historian and Marquette University professor Frank Klement, the dean of scholarly studies of Northern opposition to the Civil War. (Oddly, Blumenthal fails to mention Klement.) For more on such hobgoblins as the Knights of the Golden Circle—“I have here in my hand a list of half a million active conspirators!”—see Klement’s Dark Lanterns: Secret Political Societies, Conspiracies, and Treason Trials in the Civil War (1984); for more on Ohio’s Copperhead, see The Limits of Dissent: Clement L. Vallandigham & The Civil War (1970); for more on the geographical heart of the antiwar movement, see Klement’s The Copperheads of the Middle West (1960); for a posthumously published collection of essays, see Lincoln’s Critics: The Copperheads of the North (1999).

Frank Klement was a product of the University of Wisconsin’s legendary history department and shared its populist-Middle American orientation. He demolished the myth that the Copperheads were disloyal pro-Southern traitors. By and large they were just Democrats: some rank partisans, others honorable dissenters.

Significantly, Frank Klement came of age as a historian during the Truman-McCarthy Cold War Red Scare, which he viewed as a witch-hunt. This surely colored his view of the Copperheads, for as Klement told an interviewer, “You can’t separate a historian’s philosophy of life or the era in which he lives from his scholarship.” Ominously, in our own day, shadowed as it is by Bush-Cheney-Obama wars and see something/say something paranoia, the academy may be tilting back toward a view of the Copperheads as treasonous fifth columnists who ought to have been rounded up, a la the Japanese-Americans who filled FDR’s West Coast internment camps, or the protesters of our day who are confined in Orwellian-named “free speech zones” if they dare grumble over Democrat-Republican policies.

We live in a time and in a country which finds principled dissent of the sort exercised by Eugene V. Debs and Abner Beech almost incomprehensible. In one sense, freedom of expression knows no bounds: Internet pornography, snuff-game videos, libelous tweets—laissez faire, man. But with respect to politics, art, culture… seldom in American history have the limits of permissible speech been so narrow, so constricting. True, our Eugene Debses aren’t usually thrown into jails, but nor do they become cause célèbres, like Debs. Their prison is the red state-blue state idiocy under which the limits of acceptable opinion are demarcated by Barack Obama and Mitt Romney, and writers live in the fear (which, I can tell you as one who has long worked with members of the DC punditocracy, absolutely paralyzes careerists) of saying the wrong thing and running afoul of the hall monitors and tattletales who police American discourse. Harold Frederic—and Edmund Wilson and pretty much any writer on American subjects who is worth a damn—does not fit the liberal-conservative straitjacket. The very premise of “Copperhead”—that some decent men of the North resisted Lincoln’s call to arms, whether from commitment to Jeffersonian Democracy or wrongheadedness or pacifism or the awful presentiment that war would remake the country—enrages the enforcers of opinion orthodoxy, who insist that there is only one acceptable narrative (and a boring one at that) of American history: nationalist-consolidationist and social democratic at home, and world-saving-militarist abroad. There is no room in this carefully monitored and barren storyline for Abner or M’rye or Jeff Beech, or even Jee, Esther, and Ni Hagadorn. These men and women have been written out of American history. This film lets them back in.

“Copperhead” does not end with an affirmation of the Union, as convention would dictate. Nor does it end with an affirmation of disunion, as would a pro-Confederate film. Instead, it ends by affirming the Corners, the settlement of the Beech and Hagadorn families, as superior, in the lives of its inhabitants, to those larger countries. It reminds us that a patriot should never boast of the largeness of his country but rather should take pride in its smallness.

Peace, community, dissent, respect for rural Christianity: these are “Copperhead’s” themes. And they are as American as Crazy Horse, baseball, and Jack Kerouac.

Bill Kauffman is the author of ten books, among them Dispatches from the Muckdog Gazette and Ain’t My America. His screenplay for Ron Maxwell’s film “Copperhead” is available in print.