This is a euphemism meant to convey how fortunate we are that civilization has advanced to the point where splitting the atom can but used to generate electricity. I'm sorry that it went over your head.
I encourage you - and anyone - to read the excellent book:
_The Making of the Atomic Bomb_ [1]
... and, in this case, to pay special attention to the multiple chapters describing in painful detail just what is involved in refining and extracting Uranium. As in, cubic acres of land mechanically and chemically processed to extract ounces of material ... which is then sent to enormous production facilities, at tremendous cost, only to begin the refinement process.
It is an incredibly long, dirty and energy intensive journey and I am not sure if the ledger of carbon expenses properly accounts for these steps.
I have spent a lot of time in areas that have been impacted by uranium extraction, including wandering around the four corners area and discovering old uranium mines.
Combined with seeing how the extractive energy industry has treated old wells, where they do everything in their power to abandon them and put the burden of cleanup and mainteance of that remediation onto the public, I simply have no faith that nuclear power is "safe" as long as it's private industry doing the work.
