A very small minority in the world has access to information about the ecology or understands it. The burgeoning third world population is a big cause of deforestation and the developing nations are using environmentally damaging materials and fuel in their attempt to become richer. These are things that have resulted from policies by the west since the end of WWII. A very different direction was an option at the time, but instead this disasterous situation has occured. The third world population has grown so quickly because of the West's financial input. The developing nations have relied upon getting technology sold to them by the west, when there was once the option of denying it to them. The west makes some feeble attempts to reduce its emissions but it is useless compared to the increasing pollution and deforestation from the developing nations. Whether the west had leaders who brought this about or whether they instead had leaders who would have made much better decisions was all a matter of which world view would prevail around this critical time.
The third world is like a cuckoo being fed by the west. It is consuming the planet. If the west stopped feeding India, China, South America, etc and giving them technology to prop up food production, medecines, training them and educating them, they would all just die. We should let them "wither on the vine" if we want to save this planet. A cruel decision, to prevent an even crueler fate.
Another analogy: the lifeboats on the Titanic. Everyone can't be saved so you must use triage, discriminating about who lives or dies. If this isn't done now, while it is manageable, ecological destruction will lead to starvation, which leads to dictators, which leads to wars of extermination. Nature will then restore its own balance. This time it could be the Americans being exterminated by the Chinese. Historically racially mixed nations lack the cohesion and altruism to withstand pure races.