I have no strong opinions yet in the argument over whether or not the USA conspired to sabotage the NS pipelines. I'm just here to point out that secrecy is not a required part of a conspiracy. The literal translation of "conspire" from Latin would be something like "to breathe together", insinuating a synchronization of movements, a plotting together.
But, in our world today, all conspiracies (both confirmed and theoretical conspiracies) seem to get bucketed together. And so in common parlance, as soon as a thing is publicly confirmed as actually happening, in most people's minds it moves out of the "Conspiracy" bucket into the "History" bucket. But that's just a loss of language on our part. As always, my go-to resource in recovering the meanings of English words is Webster's 1828.
Did you not read the quote?
Besides which, the US unilaterally gives itself the right to do these sorts of things at its own discretion on a regular basis.