[rramadass]

You have read the opposite of what i meant in my post !

Your question was; Why do you suppose that European population density is sustainable all over the world? Presumably the sustainable population density is going to vary with climate and geography ?

"It is not" w.r.t. the first one and "Yes" w.r.t. the 2nd one. Diamond's books were pointed out because they were the most popular ones showing the influence of Geographical Latitudes on the spread/sustainability of Human Civilizations.

Coming to my point; our mastery of technology has enabled us to overcome "natural" limitations in a given geographical area, human potentialities and thus our relationship with the "planet"

What i meant was that ever since the start of the "Technological Age" i.e. the industrial revolution, we have gained power to drastically change our environments to sustain larger Human populations (eg. in the extreme northern latitudes, desert regions, megapolises in the already densely populated regions etc.) which Nature by herself would not have allowed. Now add the influence of Technology to extend Human lifespans and potentialities and you realize that our very "technological progress" is now our greatest danger to survival. Nature no longer has the upper hand (other than infrequent occurrences like natural disasters etc.) and our stewardship of Technology is not well thought out. Though https://en.wikipedia.org/wiki/Criticism_of_technology wikipedia page is not well written, it points to authors who have thought about the detrimental influence of Technology on Society.