Missles are objectiles, that are fired by a Spaceship or Aircraft, which will explode by touching something.
Rockets are objectiles, that are fired by a RocketLauncher or RocketSilo. They are huge, are High-Explosive and can do alot of damage.
So, actually you are right. It has to be a missle and not a rocket.
But, if we change it to missle, does that change the game?
Answer is no, only the name changes and it is logical now that it is called a missle.
But, cauze you are the first who says this, it looks like nobody cares about it and it is not annoying to everybody.