> no rational reason for the West to destroy the pipelines, outside of strained conspiracy theories that the US wanted to stop Germany from buying gas from Russia and buy it from the US

What makes it strained? Even if Germany didn't buy gas, and wasn't planning to buy gas, that could change any time. Now it cannot.

The gas shortage in Europe has only just begun. We will suffer from it over the next several years, Germany more than most.

Saying there was never any chance of a change of policy in Germany is not serious.