History is being written very, very quickly these days....
Very true. "Tipping points" for real harm can be hit suddenly and without noticing until after the fact. I've never been a leaf waving greenie out to yell "the sky is falling" and worry about the lot of every possible protozoa species that might be isolatedly threatened by major projects that obviously benefit many human beings. Further than that I'm (barely) bright enough to recognize that much of the sound and fury thrown the loudest often really means nothing.
After all, it was only a generation or so ago that the doomsayers were warning us of "Global Winter" scenarios if better ecological and environmental standards weren't practiced. Global Winter begat Global Warming and, as these things go, such are too easily dismissed. Then, what the hell do you know, some of the crack pots turn out not to be crack pots after all. And after much study of the science presented, and much time for the science to become mature, you suddenly (and perhaps belatedly) realize that the science finally became understandable barely in time for it to do you a hell of a lot of good.
Mass cullings of any species are worrisome. I do believe there are lines to be drawn. In fact obvious and relatively simple lines when those species truly are more intelligent, aware, and have the ability of singular characters and interests within their own societies. That as less informed beings ourselves we may not have understood their character or place 100 years ago is irrelevant to what we understand know. Part of our own advance and improvement has to be a willingness to simply admit our past mistakes and move on from there. Unfortunately, in many areas, that honest introspective reflection isn't something that the Japanese have proven especially good at (nor many other nations of people). Hopefully that won't always be the case.