[alloysteel]

The Rosenbergs were Communist spies, in the hire of the KGB, who knowingly and willfully provided key information to the Soviet scientists that probably accelerated the atomic weapons program of the Soviet Union by a matter of years, if not decades. Single-handedly, this pair spread the spectre of nuclear proliferation over the entire world, and we lived in the shadow of that for half a century.

[Eric in the Ozarks]

Completely correct. What the Rosenbergs did gave the Soviets ten free years of research, courtesy of the USA.
"Humankind," indeed...