Submarine Cable Map -- 99% of Daily International Telecommunications Go Through Here
In Sea Power (2017), a book on admiralty law and the maritime history, Admiral James Stavridis claims that satellites, cell microwave towers and copper phone wire all carry but a fraction of the Earth's Internet traffic compared with deep-see fiber-optic cable.
It's called SLTE -- Submarine Line Terminal Equipment, and all advanced industrial nations -- the US, Russia Federation, China -- reportedly have the ability to monitor, exploit, damage and destroy the cables.
One writer in the National Observer (which one isn't specified) observed tht to practice hybrid warfare -- which Putin has cyber divisions in place to do 00 the ability to cut cables at will and at depth gives one a powerful weapon ... the ultimate denial-of-service cyber weapon."