[dosman33]

I was under the strong impression that sea floor mining was mostly invented as cover by the CIA to operate the Glomar Explorer for the purpose of retrieving a crashed Soviet submarine with nuclear warheads on board. https://en.wikipedia.org/wiki/Glomar_Explorer

The US petitioned the UN to open up international sea floor mining rights as part of the lead up for this project. They made up a fake educational film for high schoolers about Glomar as well: https://www.youtube.com/watch?v=qXUqUpfzgxQ

[kragen]

I think manganese nodules really are a potentially lucrative source of metals; the CIA didn't want to use a cover story that was transparently ridiculous, and there were many excellent Soviet geologists and mining bureaus.