> if even achievable with current technology
Launching a nail bomb into orbit would've been possible as soon as we were able to get into space, the only question is motivation. A terrorist state, say North Korea, threaten the rest of the planet and demand concessions once they're able to get any significant mass into orbit.
I'd say intentionally destroying space assets etc should be considered an act of war (compare attacking another nation's ship in international waters), NK wouldn't have a chance and they could be put into space lockdown where any launches are intercepted.