That's an important comment. So, for amateur rocketry like this, in most countries you'd either need to get a license, or find a suitable boat and assemble and launch the thing from international waters.
But I think if you can arrange a launch from the ISS, then getting a license should also be doable.
While there are some people who are either scared of those who push the boundaries or see terr'ist potential in everything, there is a common belief among the real amateur rocketry community (i.e. Armadillo Aerospace, XCOR, etc.) that a rocket, guided or not, is simply a transportation system. A missile indeed implies an engine (jet or rocket, guided or unguided) plus a warhead.
Reverend's hypothetical device is an actively guided rocket. Rockets with just fins are passively stabilized. (Active stabilized vs. active guided is a matter of semantics and context.)
Saturn V: actively guided rocket, no warhead, not a missile.
Tomahawk: actively guided missile (rocket booster, turbofan cruise), has a warhead
During and after WWII there were also unguided missiles.
Guided Rocket... Sure, but not missle. A Missle implies there is a warhead on it. Some rockets have warheads too. Also I don't believe compressed air rcs would work nearly well enough in the atmosphere to be able to guide it. guided missles change their trajectory after being launched. the rocket i described only uses RCS to align itself and start a spin. after the main motor fires the RCS does nothing.
(sorry had to delete other post)
i don't see it as guided anyway, the guidance system is never used at the same time as the rocket motor... this is more like a targetting system that uses RCS to line up for the burn. once the burn starts the rcs is completely inactive.
fins only offer stabilisation in the atmosphere, without that, we need something else, in this case the rcs is used to get a fast spin going along the central axis of the rocket so when the motor fires, a slight variance in the thrust vector won't severely and negatively impact the flight.
This would probably be the epitome of 'model' rockets if someone did this. Come to think of it, there's probably enough combined knowledge, manpower, and available dedication of this forum, that if we wanted to (and had enough money), we probably could do it...
Well As far as laws you have your countries laws if you launch it in that country and international laws which to be honest appear to be relative or more akin to agreements then anything.
So find a Island or place a boat in international waters and you would be okay, but that doesn't mean that some country Russia/ China / Japan / US / the European countries & on and on would not believe that your rocket would be threat if it malfunctioned and take actions to prevent such an occurrence.
Now if you could launch it and pack it with enough electronics it would be possible to get a payload to the moon and on the surface safely.
BUT that would require a serious AI. And as far as the rocket itself, doable.