The NS pipeline is 1.6” steel, with a 12” rebar-cement casing. Its 70m below the sea
I’m no expert, but would probably need several hundred lbs (minimum?) of high explosives. Whoever did it also needs ability to get far away and detonate remotely.
I wonder who could manage such a job?
Maybe there were “risers” for maintenance access and that is what was hit?
/wild speculation
“I’m no expert, but would probably need several hundred lbs (minimum?) of high explosives.”
Not necessarily, because all of that reinforcement is just there to deal with the pressure that exists at that depth on the seabed. It’s not “available” to deal with any extra stresses on the pipeline from an explosion. Just a little bit more pressure than expected would probably be enough to exceed tolerances.
CIA could certainly do it. Who knows with a rogue bunch like that it’s hard to tell what master they serve.
Could a manned submersible do it?
One of yours.