Qapla' and well met, everyone!

I am currently researching for a paper on the topic of crusade and crusading in Sci-Fi and Fantasy and come to you in search of wisdom.

T'Kuvma is an unusual character of his own, but he takes his religiousness truly to another level. He picks up a theme not commonly heard of in Star Trek when he describes (ST:DSC, S01, Ep01: "The Vulcan Hello") the fallen Torchbearer as "machoq'eghmeH maghobtaHvIS HeghwI' wa'DIch ghaH." ("first to die in our crusade for self-preservation").

Hence my question: Which is the word translated as "crusade" here, and what root word does it derive from? I doubt it has anything to do with crosses – what is the Klingon idea behind holy wars?

(I was going to say "qatlho' in advance", but that does not sound like the True Klingon Way…)