> Realistically only US and Russia have the capacity to do 3 attacks like this simultaneously.

I'm no military expert but why? From reading about the pipeline, sections of it are between 80 meters and 110 meters deep which technical scuba divers can reach and the subsea blasts were equivalent to 100kg of dynamite.

Seems to me basically any country could wrangle up a decent sized boat, a few technical divers, 3 100kg bombs, and some time delayed chargers and planted bombs on the pipelines weeks or even months ago.