Absolutely, BH! It continually amazes me how stupid the human race is regarding our environment. Somehow, mankind has always supposed that the vastness of nature's resources cannot be depleted, and thereby has wrought the type of spinechilling destruction that successful horror movies are made of!
How could the gargantuan volume of the oceans be polluted by the madness of man's non-biodegradable plastics and the terror of giant oil-spills?
How could the pristineness of space be packed with waste material that threatens every spacecraft entering the orbit of earth?
How could mankind possibly cause the tremendous recoverability of the earth's atmosphere to fail?
Or large parts of the mighty ozone to be removed?
Or the temperature of an entire world to rise?
Or
billions of passenge pigeons to be wiped out in the space of a century, using relatively primitve rifles?
Or ... ... ...
Sometimes I can only believe that the majority of humans are so blinkered by their tiny personal-bubble of a world, and hence their incredible selfishness, that they either fail to understand that the world is in jeopardy, or they actually care very little that it is.
Increasingly, though, I feel that more and more people are suddenly awakening to the fact that, if nothing imminently is done to save our planet, they may just awake one day to find it is irrecoverable (if it already isn't!

). Damage control is never a wise way of doing business. However, we have no choice really, for the amount of damage - as you suggest, BH - that has already been done is already at lethal levels!
However, there is a slim hope still - if the minority (those special souls that appreciate the magnificent Earth we have been blessed to be born on) can sway the majority (those less-interested homo sapiens that I alluded to earlier). It is a mighty task, but so was the topling of communism in the Soviet Union or the recovery story of the white rhino from the brink of extinction; and those were somehow achieved, mainly due to a few people's untiring efforts to bring their dreams to reality!
I pin my hopes to the unfathomable magnificence of the Creator, and to His great plan of existence on this Earth - Mother Nature. They will find a way, but we need to assist them by slowing - and even ceasing - the mindless destruction of everything good and important around us. Otherwise, I'm devasated to say, humankind will be sacrificed on the altar of continuing life on Earth, albeit without us!