Simon, the host of ''Weekend Edition'' on National Public Radio, draws on his background as a war correspondent in this searing first novel, which traces the experiences of a young sniper during the siege of Sarajevo. Before the war, Irena Zaric is a typical cosmopolitan teenager: a star basketball player, obsessed with Sting, Lady Di and Johnny Depp, she sneaks an occasional joint and carries on a furtive, casual affair with her coach. Then the Serbs advance, intent on purging Bosnia of its Muslim population, and Irena flees across the river with her family. Simon is unsparing in his catalog of war's cruelties — as the siege drags on, the Bosnians are reduced to burning furniture for fuel and eating the worms in their macaroni — but his real achievement is in realizing that even as she trades a basketball for a rifle, Irena remains 17 years old, the kind of girl who packs purple nail polish and a teddy bear for her descent into hell. The result is a portrait of resilience, punctuated by mortar blasts and Clash songs, and a tragicomic study of the moral ambivalence war forces on its victims. ''I'm kind of a pacifist,'' Irena tells the man who recruits her as a sniper. His reply: ''So am I. When the world permits.''
