The radioactive particle is too dangerous and implacable for fallible humans to fool with.
"Despite the best efforts and intentions of the people of the United Nations," said Jacques-Yves Cousteau, addressing the U.N. in 1976, "human society is too diverse, national passion too strong, human aggressiveness too deep-seated for the peaceful and the warlike atom to stay divorced for long. We cannot embrace one while abhorring the other; we must learn, if we want to live at all, to live without both."
Pandora opened her box, of course, and Prometheus stole the fire, Perhaps these things are inevitable, given the nature of man and matter.