[Keflavik76]

Another possibility is that the P8 used a depth charge set to explode near the bottom of the ocean in close proximity to the pipeline. Check out the armament list. 

Boeing P-8 Poseidon Maritime Patrol Aircraft | Military-Today.com

[MomwithHope]

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[LonePalm]

All nuclear depth bombs deployed by China, France, Russia, the United Kingdom, and the United States were withdrawn from service in or about 1990. The W44 weapon used in the US Navy ASROC was withdrawn from service in 1989 as improvements in ASW torpedoes made it not worth the effort.

If someone used a nuke we would have known it immediately and there would be residual evidence.

Again, there are more certain, less observable, and cheaper ways to accomplish this task than dropping a weapon from a US Navy aircraft.

I'm not saying that it wasn't the US but unless this thing was laid on in a BIG hurry there are better ways to do it than using a Naval aircraft.

WWG1WGA

Garde la Foi, mes amis! Nous nous sommes les sauveurs de la République! Maintenant et Toujours!
(Keep the Faith, my friends! We are the saviors of the Republic! Now and Forever!)
LonePalm, le Républicain du verre cassé (The Broken Glass Republican)

[CJ Wolf]

Boom!

[numberonepal]

I wonder if the HAAWC system could deliver a depth charge.