How about a Georeezney? It would be the end result of Bush's finger on the trigger and him, Condeleeza Rice and Dick Cheney getting melded together. Not only is that terrifying but it's damn near indestructable! Look at all the damage thus far and they're still separate entities!
Anyway, in a vaguely similar note, what about a soldier who's grossly deformed from a war, his kevlar fused to his body in a blast. Soldiers are supposed to be in pique physical condition, making them strong, the kevlar would make him nearly indestructible, he could become MIA but gets a little vengeful/spiteful and now you have a homegrown soldier in the battlefield that's pissing on the ally on top of the enemies. Almost like a Frankenstein monster but the guy never died. Makes for a more "realistic" type monster although to make it a little more marketable, you'd probably want to use the enemy as the monster, getting pieces of a tank fused to his body and now we have this near indestructable enemy that we can't fight.
Yeah, I don't know what it is with me and the mililtary lately. I don't even write military stuff, except for my novel but it's not your basic issue mili-drama.