When massive battles are staged for war movies it can be a major problem gathering historically accurate hardware for the scenes. Many classic weapons systems are unavailable for film use either because there are no more functioning examples or the equipment in question is owned by hostile states who aren't going to allow Hollywood to play with their toys. So what's a producer to do? Make the most of what you've got. If all you have is friendly hardware, then you issue it to everybody. Granted, most people aren't going to know the difference beyond a few military hardware aficionados.