>>>Russia appears to believe that cutting off gas to Europe will end European support for Ukraine, and therefore has an obvious incentive to cut it off. Russia has incentives to make this look like it isn’t Russia’s fault
Russia had already done the former by basically "turning off the tap", and already argued it wasn't their fault because they were willing to supply gas to Europe as long as Europe paid in Russian rubles. They were also using the gas supply for political leverage:
"release our frozen assets and we'll turn the gas back on"
"pay in rubles and we'll turn the gas back on"
"stop sending weapons to Ukraine and we'll turn the gas back on"
Now they physically CAN'T do any of those things, so this is a massive blow to what little bargaining power they hoped to retain through the winter. If there is any nation that is harmed by the physical destruction of these pipes, it's Russia.
also a lot of analysts have been predicting social discontent in germany during winter due to the gas situation. russia, i immagine, would have been hoping that societal pressures would force the german government to reconsider its position on nord stream ii. turning on the nord stream ii pipeline was a practical solution to a freezing problem in germany. after blowing up the pipeline this solution no longer exists (at least not in its simple form of "turn on the tap") thus also taking away a key possible demand for any potential protests
One possible explanation is that Putin wants to prevent a possible rival from winning over oligarchs by promising to make agreement with the eu. Many oligarchs are losing a lot of money on this war and it is likely that a coup that replaces him with a more friendly leader could ease up the sanctions. Without the gas leverage this option is less likely. There are clear signs that Putin is very paranoid of being replaced in the near future.
Several of the Russians I talk to think Igor Sechin is the one maneuvering for a palace coup. There's been a lot of "close Putin allies" who have died since the war started. Sechin runs Rosneft, so if anyone is positioned to "turn the gas back on" it might be him. If he was shopping around the idea "let's get rid of Putin, turn the gas on, and get back to printing money again"....Putin blowing up the pipeline as a necessary evil to kneecap Sechin......that sounds possible.
Russia had already done the former by basically "turning off the tap", and already argued it wasn't their fault because they were willing to supply gas to Europe as long as Europe paid in Russian rubles. They were also using the gas supply for political leverage:
"release our frozen assets and we'll turn the gas back on" "pay in rubles and we'll turn the gas back on" "stop sending weapons to Ukraine and we'll turn the gas back on"
Now they physically CAN'T do any of those things, so this is a massive blow to what little bargaining power they hoped to retain through the winter. If there is any nation that is harmed by the physical destruction of these pipes, it's Russia.