[rabidrat]

Actually, the bomb and its design and construction require so much tacit knowledge that we might be on the verge of uninventing it already.

https://www.journals.uchicago.edu/doi/abs/10.1086/230699

http://www.dtic.mil/dtic/tr/fulltext/u2/1018881.pdf

http://public.lanl.gov/bsims/pdf/4S%20tacit%20knowledge.pdf