Why have Geneva, and other interantional conventions, been so thoroughly ignored in the wars following the disintegration of ex-Yugoslavia: because of the very nature of those wars, because of the immorality of the leaders, because of the breakdown of the institutions and public decency, because of the hatred that the war itself produced, because of the memories of the victims of the Second World War, or because of the build-up of violent tendencies in the individuals and the army?
All of the above, except the very last item. "Built-up violent tendencies" most certainly always exist within the individuals, but it can only surface and actualise itself when the opportunity and the excuse arises, and these are contained in the other causes listed above. Besides, about which actual individuals are we talking about here, and how many? Every society always has "individuals with violent tendencies". The only question is the one of percentages and excuses.