They definitely didn’t get it right the first time. (Library of Congress Prints and Photographs Division)

Crowds turned up with picnic baskets to watch the battle from nearby. The war, they had heard, would be heroic and swift; the battle picturesque and decisive.

Soon, they were fleeing the scene in terror along roads choked with wounded.

The battle was a Confederate victory, thanks in large part to a dour, lemon-sucking fellow named Thomas J. Jackson who held his troops in position like a stone wall, earning himself the moniker “Stonewall.”

Now it’s still hot in July, and other men in equally scratchy, ill-fitting uniforms are marching in dull formation toward their inevitable conclusion. Why stir in this weather?

It’s a reenactment.

They say that it is psychologically unhealthy to spend a lot of time dwelling on things that have gone badly in the past. There’s a word for that, and that word is “Civil War reenacting.”

Reenacting is hot and dirty work.

I know. Nearly a decade ago, I reenacted the battle of Antietam, although I was removed unceremoniously from the field for not wearing historically appropriate footwear. For me, the one surprise of these reconstructed conflicts was that the Confederates had not managed an overwhelming victory. There seemed to be so many more of them.

There are certainly Union troops present. But in general demands for a do-over seldom originate from the winning side.

Why do we so enjoy retelling this story? It is not merely that we are a nation of sore losers.

The one duty we owe to history is to rewrite it, Oscar Wilde wrote. Nonsense! The one duty we owe to history is to reenact it.

There’s something remarkably democratic about reenacting, once you account for the cost of an authentic 1860s get-up and period footwear. It’s the application of DIY to history. Make history? Try remaking it.

We are all about reenacting, these days. Take back the night? Take back the History! From the Tea Party on down, this national pastime blurs the line between revival and revisionism. “This is how it really went,” we say. “I’ve been there. I have the wig.”

The Civil War is a story we tell ourselves again and again, as a nation. Abraham Lincoln impersonators ride trains into Washington on historically appropriate dates. Troops march against each other in the same muddy fields, sweaty and burdened with historically appropriate equipment. Like most familiar stories, the facts stay put, but the meaning changes. There’s more to it than just “Gone With the Wind” or “Glory. ”

The impulse to reenact is almost as old as mankind itself, as Time magazine suggests. Killed a mammoth? Let’s get a group of mediocre actors together to share the narrative with the rest of the cave. Part is reliving the victory. But it’s more than a historical highlight reel.

Standing there in your scratchy homespun on the field, it occurs to you that things might have been different. Then it occurs to you that you would like some water, and that Reenactor Greg is concealing an ice pack under his period jacket.

One of the most striking facts of that hot field in July of 1861 was that for a long time, the outcome was quite uncertain. It certainly seemed so to the fleeing picnickers.

That things might have ended otherwise sounds distinctly unconvincing now. We have all the benefit of hindsight, all the confidence that comes from going interminably over the Anaconda Plan in school. Look at the statistics! The numbers! The manpower! Inevitable.

Or was it? I suspect that if you scratch enough reenactors you will discover someone secretly hoping that It Will Be Different This Time.

The battle may be over. But history is as much a battleground as ever. Only now, often, the forces wear wigs and carry indignant loads of tea. But the Civil War will never lose its popularity as a setting for the usual battles. Was it about the need for more government, or less? Federalism? States’ rights? Slavery? Trade? None of the above? All of the above?

The Civil War was the last hero’s war. As the war wore on, this became less true. Attrition began to be the word of the day. The anaconda’s coils tightened around the survival systems of the South. Total war raged. Atlanta burned.

But for a few moments, it was both terrible and glorious. The personalities that arose out of the conflict flickered larger than life on the night sky. They still do — and if you don’t believe me, visit the “Apotheosis Of Stonewall Jackson” window at the National Cathedral. We refight the battle in the footnotes of their biographies. Abraham Lincoln has been laid claim to by more opposing forces than any small town could dream of. Robert E. Lee is embraced, then abandoned, then embraced again.

What the war meant shifts with each passing year. The reenactors aren’t the only ones out tramping along the same paths through the same rank grass.

There is a small town in Virginia called Waterford where, each year, they reenact a Civil War skirmish twice: once so each side can win. Maybe that is always the point.