Rock beats Nuke, I don't make the rules
Hypothetically, if a surface nuke can make a 100 meter deep crater, what happens if you nuke the ground above a deep bunker, send another nuke to strike the deepest point of the crater, another nuke to the bottom of that crater, and so on?
IIRC they were talking about this with operation Midnight Hammer, if strike one didn’t do it. I’m guessing there’s a point of diminishing returns once the hole gets deeper than it is wide, though.