I recall a golden age sci-fi story
Don't recall by whom, or the title, sorry.
The author's point was that people could afford behave unethically, brutally, or irresponsibly because the result of their actions was on a small scale. The plot device was: he gave everyone on earth a device that could destroy the planet (I believe it was some kind of laser gun that could send a beam to the center of the earth, or something). The theme was that mankind would either learn responsibility or destroy itself.