The Trouble with Wilderness

On page 82 of "The Trouble With Wilderness", Cronon cites a book written by Bill McKibben. In this book, McKibben claims that earlier generations did not affect the environment with their actions and that all major environmental problems are present issues caused by the current population. I have major issues with that statement. There is evidence (we even read a book on it) that past civilizations as far back as ancient times caused environmental changes and problems. While these problems may not have been as advanced as ours currently are, they certainly existed. The Romans unknowingly did quite a bit of harm to their environment. Some of our current environmental problems are probably recent developments due to today's population, but we have not created all of them. We have built on some problems that already existed that we did not directly cause; we are not completely, by ourselves, to blame. I think McKibben is being unnecessarily pessimistic and is ignoring certain facts.