Depends on which side you're on. We have rules of engagement (e.g., you don't kill noncombatants who pose no threat). Terrorists do not.
ON the history channel, I saw a nice piece about our soldiers fighing in Ramana province in iraq.
They flushed everyone out of town, chasing insurgents. Then, when this huge crowd was fleeing the burning town, they were machinegunned from the chopper. Thanks to the chpper cam, you just saw this crowd get shredded. You could see little kids in there with their moms. Just all part of the crowd fleeing.
And our forces "received some good intel on more insurgent activity in the next town" and didn't even bother to examine, count, check out the pile of bodies they had just created. The men on the ground went to the next town to do it again.
Now, I'm not sure a mama carrying a baby, fleeing a burning town is a combatant. You can rationalize "well, well, maybe just maybe she... " but until you ask her, you don't know. Filling her with bullets isn't cool, is it?