[voice]
[Hey, Cain talks tactics all the time.] The situation is a little more complicated than that, I'm afraid. Without giving you an entire lecture and history lesson about the war, well... normally we would have called in the Adeptus Astartes to handle it--our guys with the armor--but we didn't really have a choice. Once we realized where the daemon was about to be summoned, the airborne platoon was the only one that could get out there fast enough to have any kind of chance at stopping it.
[Rather grimly.] In this case, one of the enemy forces on the battlefield were members of the Adeptus Astartes who lost their faith and turned to the god of violence. That model of suit is tailored for their genetically engineered bodies. In essence... our side IS their supply, in more ways than one.