Matthew Connelly in Literary Hub:
Although proponents of secret science like to focus on examples in which it has benefited society, insiders from the very beginning of the Cold War worried that the best minds would not be drawn to work that they could not even talk about. Secrecy protected those involved from embarrassment or criminal prosecution, but it also made it much harder to vet experimental protocols, validate the results, or replicate them in follow-up research.
One research manager at a Department of Energy weapons lab would later admit, “Far more progress is actually evidenced in the unclassified fields of research than the classified ones.” The physicist Robert McCrory, whose own lab received millions in funding in partnership with Lawrence Livermore, Sandia, and Los Alamos National Laboratories, was even more blunt: “Some of the work is so poor that if it were declassified, it would be laughed off the face of the Earth.”
More here.