>>Someone who believes it was Russia has to perform weird mental contortions

Of all the nations with interests in the area, only Germany has absolutely no reason to destroy the pipeline. There's insufficient data at the moment, but it's possible that the damage is from an explosive inside the pipes. Both Germany and Russia have access to the inside in order to perform inspections and possibly maintenance (not a pipeline person) so there are only two nations for whom it would be relatively easy to do - and Germany has absolutely no reason.

I'm not saying it was Russia, just pointing out that it might be - and that it will be straightforward forensically to determine if the pipes were destroyed from the inside or the outside - so it makes sense to wait for more evidence.

As far as the US doing this, they certainly have the capability, but saying they did it requires the same mental contortions as does saying the Russians did it.