Two different situations---and complex but, basically, one the one hand you are committing a group of people to the horrors of war and combat which is one thing and I think it can be taken very lightly--but that group is mad up of individuals each with a set of dream etc--but they come together to fight in an ethos of not letting each other down--so, at the point in time when you are just about to say charge, I think that you have to consider that in the event that one ---or a thousand of these people get killed--this cause must be worth it and that "worth it" is absolute---it isn't worth it for 1 soldier but not for ten--it means that it is not just the professional military that might be called, but future generations of children--so, it is a means of weighting the decision. Was that as poorly explained as it seems?
Conversely--when looking at what the population of the nation owes its ancesestors and future generations, the metric is flip flopped---it becomes how much do I owe it to our founders who suffered mightily and how much do I owe my children whose world and life I want to be better--how much should I stand before I take action counter ones desires and the others future. So as a nation, before we order people to their deaths, we must be sure that the cause is worth all our deaths, and before we take a course of action that compromises the sacrifices of others or the future generations, we must put a price tag on that at leas commiserate with that cost.
I need----errr, want-- a beer