Spoilers for The Dark Forest and The Remembrance of Earth's Past Trilogy below. In the book that the OP article is based on, humanity is doing anything and eve

Spoilers for The Dark Forest and The Remembrance of Earth's Past Trilogy below. In the book that the OP article is based on, humanity is doing anything and everything to prevent/defend themselves against an alien invasion happening ~400 years in the future. The character who coins "Dark Forest" theory in the book proposes sending a 'spell' (just a signal containing coordinates) to a nearby star, which is then amplified throughout the universe via "Sci-Fi science". This reveals the location of the star, and shortly after the star is destroyed by some comet-sized object moving at the speed of light. It's later revealed that some other civilization listens for broadcasts on every spectrum, decodes them for coordinates, then destroys the ones that seem to have actually been sent by intelligent life. I thought this made perfect sense - why wouldn't another intelligent species do this if they possess the technology? I personally agree with "Dark Forest" theory and think that we should /never/ make first contact (lest we are destroyed), but if we were to attempt first contact, we should at the very least have a weapon like you described available to us first.