Civil War snowball fight

Delanceyplace.com has a selection from Rebel Yell by S.C. Gwynne:

For the soldier, the Civil War was the most grim and devastating of all the American wars. Six hundred thousand soldiers died, the most in any American war, and regiments often lost the majority of their men in a single day, with Minié balls tearing through their flesh at close range, and unattached arms and legs stacked in piles in the aftermath of the battle. Winter was a respite from the horror, and the passage below describes the lives of these soldiers camped in Virginia in the brief, quiet interlude between the terrifying battles of 1862 and 1863. There was an unforgettable moment when a hundred and fifty thousand soldiers from the two opposing armies directly across the Rappahannock River from each other joined together in song: 

Though there were duties to keep the men busy that winter— drilling, as always, the occasional review, the building of defensive works on the high ground of the south bank, and the usual run of camp chores— there was also a good deal of free time. Mostly, that winter, there was just talking, a lot of it, in the tents, around campfires, on long walks and rides that their lessened duties now afforded them."Private soldiers seemed swept up in this new, lighthearted feeling. In December of 1862, they built a theater out of logs and clapboard and staged amazingly elaborate performances every night, a combination of variety shows and burlesques on officers, quartermasters, and commissaries. In one a soldier is told that his head wound would require his head to be amputated. He replies that at least then he will be able to get a furlough, only to be told that his headless body is needed as a decoy to fool the enemy. The grandest show of all took place in February of 1863, put on by the Washington Artillery with music by the 12th and 16th Mississippi Regiments. Programs were printed in Richmond, Virginia, and people came from twenty miles around to see it. Though General Lee sent a letter of regret, Longstreet and other generals attended in full dress. The main feature was titled Pocahontas or Ye Gentle Savage, which brought the house down several times. The show concluded with a thumping rendition of 'Bonnie Blue Flag.' (A month later, a group of soldiers quartered near Fredericksburg, Virginia put on an all-male burlesque in which one of the principal actors completely disrobed.) Probably the most fun the soldiers had that winter were the snowball fights. Many of them had never seen snow before. Now there was lots of it, and they knew just what to do. Every time it snowed (which was frequently) there were battles, usually involving small groups of soldiers. But, on at least one occasion, they mounted a fight on a massive scale. Two armies were formed, of 2,500 men each, complete with authentic generals, colors, signal corps, fifers and drummers beating the long roll, couriers, and cavalry. They conducted head-on assaults and flank attacks. There were probably demands under flags of truce, and fortifications everywhere. 'It was probibly the greatest snowball battle ever fought,' wrote one participant, and showed that 'men are but children of larger growth .... ' If all battles would terminate that way it would be a great improvement on the old slaughtering plan.' Robert E. Lee, who came out to observe the battle, was struck by several snowballs. The Richmond, Virginia newspapers each devoted several columns to accounts of the fight. The sweetest and saddest moment of this dreamy season came one evening when several Union bands appeared on the northern bank of the Rappahannock River to play some favorites, songs such as 'When This Cruel War Is Over' (by far the most popular), 'Tenting Tonight on the Old Campground,' 'John Brown's Body,' and 'The Battle Cry of Freedom.' Thousands of soldiers in groups on the hillside sang along, while the rebels listened. Finally the Confederates called out across the river, 'Now play one of ours!' Without missing a beat the Yankee bands pitched into 'Dixie,' 'Bonnie Blue Flag,' and 'Maryland, My Maryland.' They ended the concert by playing 'Home Sweet Home,' with hundred and fifty thousand men on both sides choking up as they sang it.

Rico says this will not happen in Iraq or Afghanistan, though there'd be enough snow...