There is something you are missing obviously. Naval engineers are not dumb. > it shouldn't be hard to track and aim a 30cm object at 100 m with a laser that is

There is something you are missing obviously. Naval engineers are not dumb. > it shouldn't be hard to track and aim a 30cm object at 100 m with a laser that is moving +/- 5-10 meters at a speed of 5m/s Boats don’t move only in one direction. They have side-way vibrations along the three special axis and constantly rotate along two. The 100m is extremely close for two boats and I think you don’t realise what a heavy sea looks like (understandable if you have never been far from shore). Navigating in nine meters high waves is not exceptional for a military boat. You are constantly losing line of sights with distant boats. Keeping a laser on something fast is doable (that’s part of what an optical targeting system does) but staying fixed on a small receiver gets tricky. I don’t think the win in bandwidth and latency justifies the hassle which is why I don’t believe ship-to-ship laser communication will ever happen. Ship-to-space however, that wouldn’t surprise me.