h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

What is just? What is the quality that divides justice from injustice? Once that is sufficiently defined, the question of whether a decision is just or not is a simple one.

I don't think we are talking about what is just - fair, proper, correct, according to the law/society's rules.
Rather, can one justify - warrant, show good reason for - war. Having to justify an action implies that it is not generally viewed favourably.

On the other hand, having read a few more conversations, it seems that people feel they can justify a war if their society deems it just.

Then how does the society determine that? If it's expedient? If there is an appropriate excuse, such as 'They launched twenty SCUD missiles at our ally'?

I think I have to reverse what I said in my first posting. Those in power seems to have no problem producing reasons for going to war, i.e. justifying their decisions.

It's a different matter, really a question of personal opinion, deciding whether or not they are 'right'. I don't think war is ever right & feel that I could never support one. However, there is the possibility of a situation where I might choose to condone it as the lesser of two evils. Unfortunately I doubt that I will ever have a real choice as with our current political system, we are merely the pawns in the hands of the politicians.
As far as I know, there are no laws or constitution in the UK determining the cases when war is justified.