It would be a MAD type scenario because you would know the firing point and be able send a response torpedo towards it.
I don’t know about that. I’m not sure I can get a non classified answer here, but how close can you pin down a passive sonar signal at 100 miles? I cannot imagine it is good enough for a targeting solution.
Of course on the converse, I cannot see how a torpedo in a curtain of bubbles will be able to detect anything outside for guidance, and there’s no way you are going to have a tethered torpedo at this speed or range.
Guidance overall could be the limiting issue for how serious a threat this really is. Perhaps that limitation is why they have even brought it into daylight. Could be they have already determined that the military uses are impractical.
There’s a lot of interesting questions surrounding this tech.