- is never allowed. You are wrong. Only if in a situation of war a major military target is bombed and a civilian bystander is targeted by accident it is not considered to be a crime. But this is no excuse to bombard an UN school, for example, because there might be a some enemies inside, knowing that many civilians are inside there. This is out of proportion and considered to be a crime as well. It is not allowed. Civilians are protected by the law of war. There is no excuse to bombard civilians and Hiroshima was a big crime and the operation 'cast lead' was a big crime too. Since world war too law has developped and what has been done in former times is no standard for today. But there is no doubt, that the US has done war crimes in Afghanistan and Irak as well.
UN to hold off on separate Afghan bombing probe for now (Reuters)
from the article: Police release rabbi arrested for inciting to kill non-Jews