In Afghtanistan, the Taliban represented well under 1% of the population(1). In WWII 31% of the German population, and 9% of the American population, were in military service. Those are just two very different wars, fought at very different scales.
A good example of this is in WWII it seems that it was fairly common for planes to strafe farmers and their equipment when they got an opportunity(3). In Afghanistan this would be incredibly counter productive, as so few Afghans were actually fighting. But in WWII? When a full 1/3rd of the population is in the military - and much of the rest is working in the industries necessary to keep the military running - ethics aside, it's easy to see how anything that reduced food supplies would have a direct effect on the effectiveness of the military.
1) https://en.wikipedia.org/wiki/Taliban - reports 60k Taliban / 37 million Afghtanistan population = 0.16%
2) http://historynet.com/what-percentage-of-the-population-serv...
3) https://www.reddit.com/r/CombatFootage/comments/3nla50/allie...
Do you consider someone that puts together IEDs for someone else to deploy an untouchable person that your need to leave alone? This person is unarmed, he's not a combatant, he's no threat to you, he just googled how to put a bunch of stuff together.
I know for myself, that if i find myself in the middle of a war i don't believe in, i'd pick my shit up and leave immediately, go anywhere else. I wouldn't just stay where i am, coding my web apps next to a goddamn bomb factory or HQ of some kind in complete denial of my surroundings, the current situation, and reality itself, while bombs are being air mailed to said factory/HQ next to me. But if chose to stay either because i want to be part of that war or am simply clueless, i can't blame anyone but me for the situation i find myself in.
Many of the Arab families in the area have a dozen children per wife, and live off agriculture, herding, or have workshops, bakeries, and the like. None of these people could even move their families, much less their livelihoods.
There is no lack of counterexamples that you could google, but as policy and as most soldiers' morals, protecting civilians - from both sides - is as paramount to us as the Prime Directive is to Picard.
What nation do you represent that "being a civilian doesn't grant you special plot shield"? I thought that was standard military procedure to avoid civilian casualties since at least the second world war.