People need to be taught that killing people is wrong. The natural instinct can be to use this permanent solution to a problem.

This is debatable I think. The vast, vast, vast majority of humans have never killed anyone, and a huge number of those who did were forced to in some way. Time and again we get combat reports that most people will simply not fire at anyone, regardless of the scenario.

It was in the sixth chapter of Men Against Fire that (Col. Samuel Lyman) Marshall made his assertions about what he called the ratio of fire. He was quite explicit: “a commander of infantry will be well advised to believe that when he engages the enemy not more than one quarter of his men will ever strike a real blow. …”

“The 25 percent estimate stands even for well-trained and campaign-seasoned troops. I mean that 75 per cent will not fire or will not persist in firing against the enemy and his works. These men may face danger but they will not fight.”

With repetition, the assertion became stronger, and nonfiring edged up to 85 percent: “we found that on average not more than 15 per cent of the men had actually fired at enemy positions or at personnel with rifles, carbines, grenades, bazookas, BARs, or machine guns during the course of an entire engagement. … The best showing that could be made by the most spirited and aggressive companies was that one man in four had made at least some use of his fire power.”