Seems like we're fundamentally agreeing on all the questions surrounding a moral view of nature, and really there's just this sticking point of history. I was making a rather general statement following on Tom's use of Native Americans as an example, but it was thus weakly applicable to Native Americans specifically. The second time around I got closer to my meaning with similar examples in other peoples' history. I think you can make a pretty good claim that the people here 20,000 years ago might have been ancestors to Native Americans, but that doesn't make them Native Americans in the specific sense we mean it today.
I found your disinction '"modern" tribal groups' to be interesting, because one definition of "modern" might be post-mass-extinction. The original settlers in N.America ecountered an environment of abundance and didn't have to think about conservation, but when the dust settled their descendents certainly had much more motivation to live in harmony with nature...which phrase is a fancy way of saying, in balance with their food supply. To quote you:
nearly all “modern” tribal groups held the land, and all that lived on it, as sacred. Part of the greater whole. Not separate pieces of a mosaic, not to be wasted, or overused without some thought to the future. This was deeply ingrained in both social custom and religious belief.
I find this very suggestive of a folklore that came out of hard practical experience. The alternative is to believe in the sheer coincidence of people across a continent being struck at random with a set of religious beliefs which also just happened to have utility in staying alive and prospering. It's simpler to posit that they're the oral tradition recording the lessons learned during the period of adaptation to a long and steep decline in game populations, and the transition from an expansionist pioneer lifestyle to a longterm steady-state lifestyle.
What the European settlers did in the 19th/20th centuries seems like a repeat of history from that perspective. They too were fresh off the boat, giddy with the wide-open spaces and mesmerized by the illusion of infinite resources, and they squandered it all. They--which is to say us modern Americans--are still learning about the adjustment from (illusory) infinite frontiers to a sustainable lifestyle. I can imagine the debates thousands of years ago sounding much like the debates today between environmental "alarmists" and traditionalists.
...what happened in the paleo era expansions isn’t in much debate, though in many cases the influx of humanity was often accompanied by drastic climate change. Such as the drying out of the southwest at, or nearly coincidental with human emigrations.
Sometimes climate change is a chicken-and-egg question, and your observation of a correlation I think often indicates a real causal relationship.
In some of Jared Diamond's work that I've read recently, he examines what happened to the Anasazi. Diamond's conclusion is that they were done-in by climate change that they themselves had caused. They deforested the region for building materials and firewood. Their extensive above-ground irrigation systems over time silted-in and raised the salt concentration of the water table to levels that destroyed agriculture. He does take into account that there was a drought that came on over a matter of many years, and takes the position that the Anasazi were by that time so weakened by the decline of their environment that they were on the edge when the drought came, and couldn't adapt to it. It may have administered the coup de grace, but the drought (in Diamond's view) didn't destroy the Anasazi.
Which of course is not to say that drought has never destroyed a human society, far from it. I'd be nuts to assert that. Just that we shouldn't underestimate the ability of humans to affect their environment. Absence of high tech doesn't guarantee absence of impact. (In other words, I think a Luddite approach to environmentalism is foolishly myopic.)