Putting together a column of vehicles takes a LOT of space, particularly if you want to space them realistically. None of my dio boards are big enough to put together a significant column beyond 3 vehicles. I suppose you could do what movies do, and digitally extend a scene, although that would be quite a bit of work.
Modern combat scenes have similar problems. 100m in 1/30 is 3.33m, too big to model easily. Tank combat is even worse (1000m =33m). You would need to use forced perspective, foreshortening and digital effects to create convincing scenes. You can model hand to hand combat in a fixed space, or one side (e.g. troops firing out of a trench into the distance off screen).