Aelf and Flying Pig, I think that you're both arguing about different things. What leads soldiers to kill civilians during wars (and let's be honest, it has happened and will continue to happen, in all wars) is indeed "temporary insanity" by any normal standard of sanity. In the situation they're put in, I would not be quick to condemn their actions, and certainly not to demand that they be imprisoned later for murder. I've met quite balanced, and indeed in my assessment, good people who eventually told me how they'd taken part in wiping out enemy villages 30 years before. They had their ghosts from that time, but at the time that was a course of action which events pushed on them...
Both colonial wars and occupation wars are like that, the enemy is also the civilian, it's inescapable. And never, for a moment, believe that massacres are done only by one side in such a war, once it stars things easily spiral out of control. Borneo must even have been less bad than Vietnam, at least there the enemy was foreign (indonesians, I believe). In this context it doesn't make sense afterwards to wish to prosecute the soldiers for a situation into witch they had been ordered!
It seems to me that aelf's outrage is also due, in this instance, to this man being the commander in the place where the massacre happened. Blame the commanders then, and the generals? Certainly it makes more sense, but commanders and generals do not exist in a vacuum. They enforce a national policy. Ultimately, blame the government? In a democratic nation, blame the people? Where should the blame game end?
I do believe that blaming someone is useful, convicting someone is useful, to at least make people more reluctant of sliding into that dangerous spiral I mentioned, in the future. But I'm not at all convinced that it would be just. Better to avoid wars altogether, whenever possible - and sometimes it isn't. Failing that, at least avoid getting entangled in other's useless wars and only worsening the situation.