hero: he-ro [heer-oh]

1. a person who, in the opinion of others, has heroic qualities or has performed a heroic act and is regarded as a model or ideal

It's not just about ignoring death. These men and women in the armed forces are heroes... if you abandon the definition above and use a more useful definition. "A person who has qualities or performed acts which are useful to the community, who can serve as models for others, so that more people will act like them." It's a Hansonian status signal.

To allow a little anthropomorphizing, a society wants to reinforce that which makes it stronger. If you were to design a civilization from scratch which is involved in wars, the first thing you'd do is grant +200 status points to everybody who died in the service of their country, regardless of if they were effective or not effective. That will get you more recruits; that will make wars easier. It doesn't matter if the words are true or the definitions are consistent, granting those bonus status points would help you achieve your goals. It makes sense for a society to do that, and it makes sense that a society would punish people who point out it's reinforcement systems.

This is how being a cell in an organism feels from the outside.