40 years ago warfare and seal training was strictly post jungle stuff. Their training in the past two decades has been focused now on dealing with middle east terrain and jihadis.
I think they're capable of doing anything they focus on, just look how they took out that guy several weeks ago......
But a large, underground facility that is literally protected better than the Crown Jewels? Better to just ignore them and let them rot. If they want nukes let them try to eat nukes. And sand. They have a lot of sand.