Russia Could Attack Underwater Internet Cables, Warns British Military Chief

So why don't we publish that in the news! @@

Can't any nation dig up the transatlantic communication cable and bring down the internet

Yes, and lots of other nations have this capability too. We have been aware for some time now and have worked (and continue to work) on physical and virtual network resiliency. Amazon, Google, MS, and many other worldwide companies care a great deal about maintaining access in the event of a cable getting cut...they're working on it too, probably more effectively than DoD.