In 1962, NASA engineers debated the merits of nuclear, chemical, and electric...

https://technivorz.com/why-do-articles-compare-nuclear-and-chemical-like-it-is-obvious/

In 1962, NASA engineers debated the merits of nuclear, chemical, and electric propulsion with all the diplomatic grace of a tavern brawl. These internal memos reveal that deciding how to reach the moon wasn't just a physics problem; it was a political one