He's likely thinking of the urban myth that over 10% of the US's power generation was used for the Manhattan Project [1] and confusing it with the cost of the p

He's likely thinking of the urban myth that over 10% of the US's power generation was used for the Manhattan Project [1] and confusing it with the cost of the project, for which estimates vary but is around $2 billion total (1945 GDP was $2 trillion). [1] http://meetings.aps.org/Meeting/APR11/Session/H13.4 http://meetings.aps.org/Meeting/APR11/Session/H13.4