While there is general agreement that only combatants are legitimate targets, the issue of who actually is a combatant is much less clear. This can be developed into two principles: This includes direct attacks on civilians and indiscriminate attacks against areas in which civilians are present. The Geneva Convention lays down that civilians are not to be subject to attack. Those who are not fighting should not be attacked as this would violate their human rights. The general rule is that only those people fighting you are legitimate targets of attack.
In World War 2 more than 50% of those who died were civilians.At the beginning of the twentieth century only 10%-15% of those who died in war were civilians.This question has become more important during the last 100 years because a century ago most people killed in wars were professionals. The practical question is this: 'Is it immoral to kill civilians in war?' An issue of growing importance