Has it even been confirmed that Russia did this? Anyone can cut a cable. This could be environmental groups. I highly doubt that Russia would do anything to a NATO air base, which would give NATO an excuse to do just what you demand.
They have been avoiding escalation with the West all the time.
The leading anti-nuclear force in the 1980s and 1990s was the Green Party, which wasn't pro natural gas at all.
Furthermore, it is now one of the most anti-Russian parties, so any conjectured FSB operation could be considered to have failed spectacularly.
The former East Germany supported left wing terrorism and some hard left student revolts, but the anti-nuclear sentiment goes through many parties and simply does not need any external stimulus.
They have been avoiding escalation with the West all the time.