User blog comment:NovaTopaz/Weapons of navies/@comment-22011788-20140604140210/@comment-11135771-20140604230927

Actually, I don't see the problem with IGBMs being fairly small. You can make an intergalactic (well, INTRAgalactic) missile by just shooting it in a direction and then letting its inertia take it near the target before turning on the engines again and guiding it in more precisely. Since there's nothing to slow it down, it could go over an infinite distance without consuming fuel (of course, that's assuming that it moves at sublight speeds, which means that it'll take forever to hit anything on a galactic scale. A warp drive powered missile would probably need to be the size Ficus7 mentioned. Speaking of which, we really need to set up some rules around how warp drives work and what their limits are...).