I've explained it in some detail before but I'll do so again.
At the moment Putin is losing a war he started. He's losing it in large part because the West is supplying arms to the Ukraine. Russia wants this to stop.
In order to do so he has 2 ways to pressure the West.
The first is nuclear weapons. In order for that to be effective he needs to convince the West he is willing to actually use them.
The second is his hold on the gas supply. Especially to Europe. To that end he has systematically lowered the supply Russia delivers to the West. Driving up prices. To the point BEFORE Nordstream had holes blown into it of cutting it off completely.
Blowing holes in the pipelines though serves both reasons. It shows that Putin is willing to engage in violence even outside Ukraine making him look unpredictable and desperate. Both serve to instill fear vis a vis Russian willingness to deploy nukes. And it also shows that he has the capability of attacking undersea pipelines that serve Europe of which Nordstream is only 2. Something that resulted in sharp increase in gas prices although neither line was operational at the time.
This idea that Putin would balk at the idea of blowing (repairable) holes in a pipeline that serves no purpose at this time when engaged in a war costing billions a month and threatening his personal survival if the outcome isn't good is ridiculous.
So is the idea that the US would blow up a pipeline not working and that supplies Russian gas which has been shown to be used as a pressure weapon on Europe, is equally so.
Europe will even if the war ends tomorrow get of its dependency of Russian gas regardless, because they have to for strategic reasons. So the US blowing up those lines is both stupid and pointless. Not so for Russia.
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