When ‘Oumuamua, a mysterious interstellar object, swept through our solar system last October, it elicited breathless news stories all asking the obvious question—is it a spaceship? There were no signs it was—although many people seemed to hope otherwise. Throughout history most strange new cosmic phenomena have made us wonder: Could this be it, the moment we first face alien life? The expectation isn’t necessarily outlandish—many scientists can and do make elaborate, evidence-based arguments that we will eventually discover life beyond the bounds of our planet. To true believers, what may be more uncertain is whether or not such news would cause global panic—which depends on how our minds, so greatly influenced by our Earthly environment and society, would perceive the potential threat of something utterly outside our familiar context. “There’s this feeling amongst the public—a very large fraction of the public—that the discovery of intelligent life at least would be kept secret by the government because otherwise everybody would just go bonkers,” says Seth Shostak, an astronomer at the SETI Institute who was not involved with the study. Perhaps it might make sense for our brains—tuned by millions of years of evolution to be wary of predators—to freak out over immensely powerful alien beings arriving on our cosmic doorstep from parts unknown. read more https://www.scientificamerican.com/article/is-humanity-ready-for-the-discovery-of-alien-life/
I'll try to find it, but there was a journal article a few months back talking about aliens ruining our civilization. They basically said no alien would have to worry about an "Independence Day" or "Ender's Game"-type invasion or attack...they just have to send a message of something like "We like and want to work with your species, but only the smart and kind ones. Unless you kill (insert a large population, like "Christians" or "Chinese" or "White People" or whatever) and ensure they can't pollute your species anymore, we're going to use our technology to shield your sun for a few weeks until you all die and then colonize your planet." That could cause widespread panic and "survival of the species" mode.
