What myth Bierce wants to debunk in "chikamague" ?

In "Chickamauga," Ambrose Bierce sets out to debunk the persistent myth that war is glorious. In the story, a little boy plays a game of soldiers, cutting down imaginary enemies with his toy wooden sword. But not far from where the boy's playing a real-life battle is raging, the Battle of Chickamauga, the second costliest battle in the Civil War, with over 34,000 casualties.
The boy is deaf and so cannot hear the intense rumble of battle in the near distance. Blissfully unaware of the horrors of war, the boy has a romanticized view of conflict, seeing it as nothing more than a big game. Even when he stumbles across the bodies of dead soldiers, he still persists in his fantasy world, seeing himself as the fallen men's commander.
It takes the burning of his house and subsequent death of his mother to make the boy realize what's really been happening. But even then, he cannot express his horrified response. As a deaf child unable to speak properly, he's reduced to making "wild, uncertain gestures" and uttering "a series of inarticulate and indescribable cries."
"Chickamauga" is generally thought to be a political allegory. The young boy represents a romantic attachment to war, all too common in a young nation whose very identity has been forged by conflict. The boy is literally deaf to the sounds of battle in much the same way as too many of Bierce's contemporaries were figuratively deaf to reason, willfully ignorant of the immense suffering and destruction that war brings in its wake.