According to defense officials, the new rules are expected to continue the long-held prohibition that prevents women from serving as infantry, armor and special operations forces. But they will formally allow women to serve in other jobs at the battalion level, which until now had been considered too close to combat.

In reality, however, the necessities of war have already propelled women to the front lines — often as medics, military police or intelligence officers. So, while a woman could not be assigned as an infantryman in a battalion or in a company going out on patrol, she could fly the helicopter supporting the unit, or move in to provide medical aid if troops were injured.