Tube Alloys was started during World War II.
Notes on verification
Confirmed by Wikipedia, a peer-reviewed academic source, and the Atomic Heritage Foundation, all independently corroborating that Tube Alloys was authorized in 1941 during WWII. [tier=silver indep_score=0.925 clusters=2 claim_tier=everyday]
Sources
- History of nuclear weapons (wikipedia)
- https://www.tandfonline.com/doi/full/10.1080/00295450.2021.1910004 (corroboration)
- https://ahf.nuclearmuseum.org/ahf/history/british-nuclear-program/ (corroboration)