I think this is a first for Keicraft (aka Kei Goto, one of my favorite designers), I've never actually seen any papercraft model from him that had or involved weapons on it.
Although he did some appliance papercrafts for Panasonic, a few car models, bikes for Yamaha, and some anime/video game characters (Alfred the Car & Meiji's Isodine the Hippo), the bulk of his work has always been about animals and family related stuff.
I was surprise to see that he did an attack helicopter papercraft for the official site of the Japan Ground Self-Defense Force or JGSDF (Japanese Army). The attack helicopter is based on the AH-1S Cobra antitank and there's also a parachute papercraft to go with it.
I think it's a good thing that his branching out, hopefully we can see more military vehicles or other weaponry papercraft from him in the near future.
Another thing, if you scroll down to the bottom of their page you can find two other models, a Humvee and a tank papercraft from designer Y. Horie - it was posted last year but I guess we missed it.