Think of it like this: While an imperative acknowledges the necessity of a particular action, justification implies moral acceptance or approval. There's no moral justification for mass ritualized murder; however, recognizing an imperative doesn't necessarily mean you condone or justify war.
It changes how you address, approach and regard it. Cheerleading is frivolous froth or dangerous goading when the war gods come. The first time you hear a mortar incoming will change your perspective or make you a demon. we unfortunately may find out soon if the cheerleading continues.
war should be faced and contemplated by those who are prepared to die. It makes wars more scarce and aggression more difficult to fund.