[Mature] What is a Justified War?

[Krillin]

The justification for war is pretty simple: there is a limited amount of space/resources/power in the world, and everybody wants more of it and not everybody gets along. Iit comes down to whether or not your nation/allies are the dominate force or the dominated - and that at times is decided by war.

That's an explanation as to why there is war. Specifically, the topic is about whether or not war is justified, and if so, in what cases?

Is a resource war justified if success means procuring the resources necessary to remove poverty in a home country? How about the removal of many forms of disease? The provision of expected luxury? Lower gas prices?

The real drive behind this topic is not so much to provide a line between a "good" war and a "bad" war, but the definition of that line itself. What objective factor, if any, provides the justification for a war?

Or is it, rather, subjective, thereby allowing a religious conflict to be justified, if one or more of the parties involved are sincere in their convictions?