I seriously doubt that a full-scale military assault on Russia is 1) going to be productive in the long run and 2) really not justified just to protect a cable. Given the ultra-big egos of donald and vladmir, any act that one might interpret as an assault would very likely result in massive amounts of firepower launching at civilian targets. Maybe I'm alone in accepting some spotting internet connection to Europe vs hundreds of thousands (or easily, millions) of casualties.
The problem from a game-theoretic point of view is that if your opponent believes you won't retaliate over something small, they can just keep nibbling small chunks. Better to have the public believe that you're super territorial and will react violently to the slightest provocation. I think Vlad and Donnie know this and incorporate it into their public images, which is part of the reason you describe them as "ultra-big egos".
But it's probably not necessary to shake a big military stick at every problem. That's been a consistent response throughout most of human history, and it rarely ends well for the folks that are not on top.
> Better to have the public believe that you're super territorial and will react violently to the slightest provocation.
That's how you end up fighting wars nobody wanted. If you threaten Armageddon over every little thing and then don't deliver, nobody is going to take you seriously when you're, well, serious.
I'm convinced that's how the US ended up bombing Serbia - the Clinton administration tried to buy a little cheap grace by threatening the Serbs, thinking Milosevic would knuckle under and that would be that. But they were ignored. More threats followed and were also ignored. At some point Clinton had to do something or nobody on the planet was ever going to believe he had the backbone to carry out a threat.
