And as for cars, like I said earlier, I am pretty much on the fence about it. I think we can look back into prehistoric times when people would throw rocks, and I think that it’s fair to say that these rocks were also weapons, but not that every rock is a weapon, but any rock can be a weapon if someone grabs it.
The same can be said for a spaceship; even if it isn’t it’s primary purpose, much like the rock, it has a high potential for destruction that can’t be ignored. A single interstellar spaceship probably has enough energy to boil all the water on earth without even pushing it.