Note how good at digging the Chinese (and a number of other Eurasian peoples) are - and have been for a very long time. A little known fact is that the PRC actually has substantial investment into Civil Defense including many public and private shelters. They LOVE digging!
They say Moscow has a second Moscow beneath where the entire city can get out of danger from nukes. Where are our population-saving bunkers? I don't want to hear any more about how Congress can be saved. That won't be much good when Congress emerges and finds their constituency has been deconstituented.