Comment by toss1

No, there is a VAST menu of effective retaliation or response measures. The response absolutely does NOT need to be exactly in kind or 1:1.

The key is that the measure must cost the aggressor more than they gain, and of course be reasonably proportional.

Plus, even if we stick to your irrelevant requirement, response is better. It is less bad to have no subsea cabling for everyone vs making no response and ending up with only the aggressors having subsea cabling.