As independent documentary filmmakers from Berkeley, husband and wife Gary Weimberg and Catherine Ryan knew the Army's press office might be suspicious of their request to interview soldiers for a film about the morality of killing. Much to their surprise, though, the Army brass not only granted access to recruits on their way to Iraq and Afghanistan, but the couple's new film, Soldiers of Conscience," which airs Thursday on PBS, also struck such a deep chord among the military, it's now to be shown in sophomore ethics classes at West Point. "They sent us a very nice, but terse, statement after they viewed it," Weimberg recalled of the military press aides who signed off on the finished product. "It read: This is approved. And, Thank you." In "Soldiers," Weimberg and Ryan focus on eight young soldiers, four of whom decide they can't pull the trigger after they reach the battlefield. Viewers may wonder why anyone with pacifist tendencies would join the Army, but each soldier has a trench epiphany - what the military calls a "crystallization of conscience" - and it's clear only the realities of wars can dredge up such emotions. The filmmakers do their utmost to ignore politics - their subjects barely mention their commander in chief's arguments for war - focusing, instead, on how soldiers marshall the will to attack. "It's not a film about Iraq," Ryan said. "Even in the wars that are supposed to be 'good wars' and fought for 'good reasons,' this question gets raised, and these stories occur."