>They keep catching these people. Interdasting.
These are only the ones dumb enough or unlucky enough to get caught. There are likely many, many more.
This is not how they secretly communicate.
How does one steer a hypersonic anti-ship missile with a range of 450km? It will need to be rather pointy to cut through the air and be made from high-temp materials. It will be very difficult to make effective terminal guidance sensors that fit in that package. And the launching ship can't send it guidance because the target will generally be over the horizon.
Sounds like they're trying to win the big-dick contest without much concern for practicality.