Excerpt from Tomdispatch:
Here's the simplest truth of air power, then or now. No matter how technologically "smart" our bombs or missiles, they will always be ordered into action by us dumb humans; and if, in addition, they are released into villages filled with civilians going about their lives, or heavily populated urban neighborhoods where insurgents mix with city dwellers (who may or may not support them), these weapons will, by the nature of things, by policy decision, kill noncombatants. If an AC-130 or an Apache helicopter strafes an urban block or a village street where people below are running, some carrying weapons and believed to be "suspected insurgents," it will kill civilians. The disadvantage of "distant war" is that you normally have no way of knowing why someone is running, or why they are carrying a weapon, or usually who they really are.
Once Americans find themselves engaged in a guerrilla war, the urge is naturally to bring to bear military strengths and limit casualties -- and the fear is always of sending American troops into an "urban jungle," or simply a jungle, where the surroundings will serve to equalize a disproportionate American advantage in the weaponry of high-tech destruction. In distant war, particularly wars where Americans alone control the skies and can fly in them with relative impunity, the trade-off is clear indeed: our soldiers for their civilian dead "including women and children."
This is not an aberrant side effect of air war but its heart and soul. The airplane is a weapon of war, but it is also a weapon of terror -- and it is meant to be. From the beginning, it was used not to "win over" enemy populations -- after all, how could that be done from the distant skies? -- but to crush or terrorize them into submission. (It has seldom worked that way.)