All of the Future War Cult's new Hunter gear has "Immanent War" in the title. The notable thing about that is the meanings of "immanent" and the fact "immanent" is pronounced the same and nearly spelled the same as "imminent", a more common word meaning "about to happen". FWC is of course all about the coming war (as well as the present war and past wars and eternal war), but given that it's in the name of all five pieces of armor I don't think it's a misspelling. Immanent (with an A) has an interesting variety of meanings, including the flip side of transcendence (whereby someone or something that goes beyond reality makes itself a part of reality, or in fact pervades and supports reality) and being all in your head.
It feels like wordplay and the kind of humor Bungie likes to use when they get the chance, and possibly an exploration of FWC's philosophy or reinforcing how mysterious or mixed-up they are, and I like it.