This song is an obvious reference to how during the cold war people were so scared of being nuked by the soviets that they built bunkers to hide in if there was a nuclear bombing.
I will hide and you will hide
And we shall hide together here
Underneath the bunkers in the night
I have water, I have rum
Wait for dawn and dawn shall come
Underneath the bunkers in the night
Underneath the Bunker was written by Mike Mills & Peter Buck & Michael Stipe & Bill Berry.
Underneath the Bunker was produced by Don Gehman.
R.E.M. released Underneath the Bunker on Mon Jul 28 1986.