Interesting.

Still, territorial waters extend for 12 nautical miles. Apparently, these satellites fly at 1100-1300 km. If ground stations (both SpaceX backbone routers, and mobile terminals) can talk to a satellite 45 degree above horizon, the satellite can connect the terminal with the ground station in a circle 1100-1300 km radius underneath (slightly less due to Earth curvature, but not by much).

Not gonna work in the middle of the Pacific, but might be good enough for many. For instance, one can sail from here across Mediterranean Sea all the way to Africa or middle East, while staying within reach of Europe-based routers. That’s assuming SpaceX gonna build them.