Slightly tangential, but "kmph" is a very confusing way to refer to thousands-of-miles-per-hour. I had to re-read that half a dozen times to figure out it wasn't going 7 KiloMetres Per Hour.
The missile may be unstoppable but you can bet it would take only a couple seconds to sink the ship and that there is a sub nearby ready to sink it. It’s unlikely to fire more than a few
