In 1998, eight years ago, I was privileged to visit Gettysburg with my husband. The American Civil War had long fascinated me by its resonances with the more distant conflict on which I worked. The Battlefield Park was astonishing. There was not one single monument, as at Thiepval on the Somme, but hundreds to individual regiments; the New Yorkers had big statues, while the men from Maine were recalled with quiet and modest stones. There were several different kinds of battlefield tour available from the huge Visitor’s Centre; we chose to ask a guide to accompany us in our car, and he proved to be a man with a particular fondness for General Meade and an eagerness to restore a reputation he felt had been unfairly slighted by the bestselling novel by Michael Shaara. We saw every scene; the Devil’s Den, Little Roundtop, vividly brought to life by the guide’s enthusiasm.

A few years later, we pulled into Fredericksburg battlefield car park, having made our way to it through a maze of malls and fast food places. My baby daughter was asleep in the back, and I sat idly by her in the pale late autumn sunshine. I heard a faint thunder of gunfire, and I looked up. Straight ahead of me was the stone wall behind which the Confederates had crouched to wreak their devastation on the Union troops as they struggled up the hill. That evening, plumes of cannon smoke hung in the air. I knew it was a re-enactment – commonsense said so – but there was an uncanny sense that history was almost too near, a sense that increased when we drove on to the Wilderness at dusk, stopping by the monument to Stonewall Jackson. The woods were full of ghosts; the trees rustled just as they must have before Jackson’s men sprang on Joe Hooker’s forces. It might all have happened yesterday.

Why was I so surprised by these sites? Because the same year, my family and I spent an hour and a half fruitlessly hunting for the battlefield at Edgehill, and another hour searching for Naseby. At the site of Naseby fight, where thousands died, a busy road tears by, indifferent lorries filling the air with brusque modernity. The local council has secured some money for a facelift for Naseby, but it will never have the loving resonance of Gettysburg, the little individual monuments put up by those who still remembered the dead as fathers and brothers, sons and lovers. At Edgehill, a nearby pub garden houses a modest panel sketchily explaining what happened. Only Marston Moor has a nineteenth-century monumental pillar and a few plastic signs. Around the pillar, the inscrutable fields stretch blandly away on every side. There are reenactors in England – the Sealed Knot society is the best-known – but they perform as and when, on school playing fields and at fairgrounds. The last Sealed Knot member I met was with a small group of reenactors at Basing House, scene of a famous siege. It was late afternoon, and no-one had been by for hours. The other reenactors wanted to leave, but their leader held firmly on in the hope that some spectators might come out of the twilight to learn about musket and cannonade. Nobody but my son and I appeared, and at last he gave way and headed for home, manifestly embittered.

Yet it is not that Britain can’t do battlefields. Travel down the road to Leicesteshire and you will find a very elaborate recreation dating from 1974 of the last battle of the Wars of the Roses, the Battle of Bosworth, in which King Richard III died shouting for a horse. Hastings is equally well commemorated. Both are diligently billed as The Most Important Battles in English History. Yet the far more important civil war battles are not commemorated. The other displays dispose of the idea that the Civil War battles are not commemorated because they are too long ago, or because they were a civil war. Something deeper is at work, a reluctance to acknowledge a difficult past, a dread of reigniting religious hatred, and perhaps above all, a discomfort with the outcome.

Let me expand. To commemorate a war, someone has to want to keep its memory alive. The American Civil War was followed by a determination to remember the fallen, a wish to commemorate the struggle for what came to be seen as human rights for the north, and to recall the moments of military glory to warm the chill of defeat for the south. Both sides evolved a clear if actually oversimplified sense of what the war had been about, and were able to turn that sense into appropriate monuments.

In the English Civil War, by contrast, people’s sense of what the war was about changed radically during the war itself. For the king’s opponents, what had once been a defence of Protestantism and Parliament as its surest safeguard became a critique of the king who had failed to protect true religion – but only for some. For the king’s defenders, an attempt to mop up a rebellion by the usual suspects became a defence of traditional rural life, parties, ceremonial. The idea that the war was about Parliament was immeasurably compromised by Pride’s Purge, which left the Commons a mere group of nodders, and by Cromwell’s dissolution of Barebone’s Parliament and his assumption of direct rule in 1654. The king’s opponents were no longer sure of what they were about. The king’s supporters, on the other hand, had no real reason to run about erecting monuments to battles lost to rebels, and may have shuddered at the idea of doing so much as we might today shun the idea of a memorial to the valour of the SS. Royalists instead endowed churches to Charles the Martyr, and there are many: the seventeenth century alone saw foundations in stoutly royalist Cornwall and Shropshire, in equivocal Plymouth and Kent, and in doubtful Suffolk. Last century, Alabama acquired such a church.

So England has turned its back on its most influential war. We might get additional hints about why from another American response to its civil war, another surprise for me. When I visited Atlanta this year, I was expecting a focus on the battle for Atlanta amounting to preoccupation. But apart form an old diorama, and Stone Mountain (now a theme park) there was nothing at all. The city has firmly turned its back on the past. I asked a few inhabitants why, and they said the past was too divisive to be remembered in an African-American city. Slaves could not celebrate the war that freed them while living alongside the descendants of those who sought to keep them in chains. Perhaps we might say the same. As long as we have a monarchy, it is hard to cheer for parliament.