Defense vs. Offense as a conceptual technical battle is ongoing, and its never decided one way or the other. If you improve on the offensive measures, the defensive side will do as well, and likewise, to the offensive side again, and this cycles over and over. Jamming, ECM and maybe even EMP may end up being used in both directions; missiles will have jamming and decoys, but so will ships.
The result is no certainty in theory and principle until all are tested in the crucible and laboratory of actual combat.
I thought we have already mentioned the ballistic missile plus torpedo idea before. I think no one has said much because no one hasn't seen any other way to properly counter it unless you are able to intercept the missile itself early with an anti-ballistic missile. And its not just a torpedo, it should be a rocket propelled super cavitation torpedo or Skvall like device. if the torpedo is wake homing, even more the problem of countering it. Typically the best way to counter a torpedo are with decoys, but if the torpedo is "smart" or uses some other principle in homing, I can see no other means but to MLRS a rocket barrage of depth charges in front of the torpedo's path.
In any case, I think torpedoes are one thing today that may be dangerously underrated.
I am always fascinated by some of the stuff the Russians use, sadly not adopted by the Chinese. Things like the Vodapad or Stallion, which as ASROC or rocket launched torpedoes, like the SS-N-14 Silex, the SS-N-15 Starfish, or the SS-N-16 Stallion.