Role of Einstein in the Atomic Bomb

Is Einstein's famous equation even relevant for the nuclear bomb? What is the relation between E=mc² and nuclear energy? What was Einstein's role in the development of the atomic bomb?

Einstein-Szilard Letter: https://rb.gy/u6f7m
Frisch-Peierls Memorandum: https://rb.gy/rxiib

Playlist Physics of Nuclear Weapons:    • Physics of Nuclear Weapons  

00:00 E=mc2
01:28 E=mc2 and fission
03:28 enter Mark Oliphant
05:08 MAUD committee
06:27 Einstein-Szilard letter
07:37 America gets serious about the bomb
08:34 Einstein letter vs. Frisch-Peielrs memorandum
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