On first-world countries and resources: that's beginning to change. Yes, on a per-capita basis, OECD nations (largely the US, Canada, Europe, Australia, NZ, Japan) consume more resources than elsewhere. China's absolutely stunning economic growth over the past 20 years has been accompanied by an equally stunning growth in resource consumption, and the country exceeded the US in CO2 emissions by 2006: http://en.wikipedia.org/wiki/Greenhouse_gas_emissions_by_the...

That said, I = P * A * T holds. Environmental impact is a function of population, per-capita affluence (resource consumption), and technology.