A CIVIL WAR soldier recalled that he wanted to "go to war like the men in the pictures . . . flourishing a great yellow sword over my head and dashing into the thickest of the fight on a furious, coal-black horse."

The men in the pictures are on display now at the National Portrait Gallery, and they say a lot about that war and the adolescent nation that entered it, never dreaming there could ever be such a place as Antietam's Bloody Lane, or the terrible Wheat Field at Gettysburg, taken and retaken four times until the wheat was cut to stubble and the bodies lay two deep.

The war in these lithographs is a storybook war. Jeb Stuart in his plumed hat prances on his steed (no mere horse, this), and his raffish cavalry gallops behind him over a decorous little cloud of dust. Old Winfield Scott, so fat and dropsical he could barely stand, let alone ride a horse, is portrayed sitting tall in the saddle, fiercely waving his plumed hat. Poor John Wool, at 75 the oldest officer in either army, is shown as a vigorous 40-year-old.

Men forget what war is like, and each new one starts as a romantic pastiche of the last one, complete with generals who think they are still fighting it. Didn't World War II start out like World War I, and World War I like the Civil War, and the Civil War like a Napoleonic campaign?

In fact, Confederate Gen. P.G.T. Beauregard affected Napoleonic curls, and one litho by Joseph E. Baker shows him in a classic heroic stance with sword and horse and a single cannonball just so, while an Austerlitz rages in the background, men drawn up in ranks with their flags and cannon beside them.

No wonder young men rushed to the colors in those first months. No wonder that two years later there were antidraft riots in New York, when people had seen some casualty lists, and leg stumps, and photographs of bodies. That mood is reflected here too, in Adalbert Volck's savage anti-abolitionist etchings and his deadly picture of Lincoln sneaking through Baltimore in a boxcar because he feared an anti-North riot.

Despite the photos, which perhaps weren't yet as widely seen as these lithos (plus the calling cards, envelopes, currency, sheet music and tobacco packs where they also appeared), the romantic view of war continued even past the death of Stonewall Jackson in 1863. There are several versions of Jackson, from the beardless youth of 1851 to Volck's delicate etching of his death mask. All show a regal, natty soldier, imposing and grave.

The reality is best described by Shelby Foote in his marvelous three-volume "The Civil War": A Northern civilian, injured and captured in the vicious early fighting at Second Bull Run, learned that the famous Stonewall was nearby. He asked to be raised up for a look at this fabled hero. He saw a man bent in exhaustion, his clothes filthy and stained from days on the road, his beard matted and muddy, his face streaked with sweat and soot.

"Oh my God . . . lay me down!" the man groaned. (And for the rest of the war, the Stonewall Brigade had a catchword, as in: "Oh my God, lay me down. Here come them Black Hat fellers!" or "Oh my God, lay me down. Beans again!")

A curiosity: As one general replaced another in the public eye, as the names and faces proliferated over the years, lithographers had to work fast. Portraits of Commodore Foote and Commodore Dahlgren are obviously the same picture with different faces and hats. Gens. George Meade and Ulysses Grant get the same treatment. One group picture even has two heads rubbed blank, ready for the next instant heroes to take their place in the august gathering of uniforms.

It's a small exhibit, but brisk and well signed. A useful insight into war and propaganda and why we fight.