I recently read an article that Google wants to build a submarine cable connecting to my country supposedly to increase overall speed and while I hope my government will never allow this kind of thing it made me curious about the actual security of submarine cables against man-in-the-middle attacks.
I tried to search that online and only found the following links:
I'm familiar with the concepts of encryption and I know that whoever does that will be able to intercept all HTTP traffic but I also know HTTPS is not unbreakable; won't they be able to see all the handshakes happening between the parties to at least do network analysis like I'm connecting to my VPN and they see my IP doing a handshake with the VPN IP and know that now I'm connecting to a VPN and be able to correlate my traffic when it leaves the VPN and much more?
So how bad would it be to the Internet as a whole if there's an active man in the middle tapping submarine cables? I see that submarine cables are obviously interesting for many reasons to many countries around the world and they pass international water space with no rules.