No conspiracy needed, SOSUS was a known fact, the Soviet Union made attempts to find and disable the hydrophones, Tom Clancy wrote many a novel in which SOSUS was mentioned or played a role, etc. It was the ocean equivalent of the Key Hole satellites, used to monitor the movements of Soviet 'boomers' - nuclear missile subs.

There is no "conspiracy" in the sense of a shadowy cabal or secret organization. But I think it's remarkable how such a huge project which must have involved the participation of dozens of governments could have been done without any press coverage or civil society involvement.

I think I also never read about that in any newspaper:

https://en.wikipedia.org/wiki/Operation_Gladio

Yes that was the point. It was good. Ukraine had an identical plan -- same as Russia had the feared plan in the SE, where state institutions failed.