Ever noticed when you deploy special forces to blow up a ship, they never return!
You can also use these brave souls as a countermeasure against torpedoes by assigning them to a fake surface target. They will cluelessly cruise into eternity while countless torpedoes will be able to lock on to them and explode (the destroyed inflatable won't sink

), you don't get that with any tubular countermeasures!
Why not just create a manned torpedo in the first place?
Well anyways, these submarine launched terrorists do the job well.
kind regards,
Paul