Countries like Australia and the US have abundant natural vegetation to absorb pollution and more fields and forests to provide the world's natural resources. They have high per capita energy consumption and hence large ecological footprints. For example, each US citizen needs 10 hectares of land to sustain themselves with resources and pollutant-absorptive capacity. But these same countries have plenty of land to meet these needs. It is countries which overshoot their footprints with resource consumption which are the villains:
'Such footprints represent a partial measure of the extent to which the planet, its regions, or nations are moving along a sustainable development pathway. ... national footprints alert humanity to the necessity of living within the regenerative capacity of the biosphere in order to ensure 'environmental sustainability'.When a population's footprint is smaller than its biocapacity it is a sustainable. Americans and Australians have large footprints but their biocapacities are large so they are sustainable. This suggests that national emissions should converge on a figure proportional to population per unit land area. Moreover, this type of policy may be acceptable to the US - in the long-run it must merely live within its biocapacity for sustainability to prevail.
Under the Kyoto protocol countries can offset emissions with 'purpose-built' carbon-sink forests. The 'footprint' formula sees whole landscapes as offsetting emissions. The global equity implications of this reasoning are difficult but, with long-run global economic convergence, it might make sense. There are attempts to refine the footprint idea to make it more operationally-sound and to account for differences in family size, land use type and so on. It then might become a key element in, for example, greenhouse gas emission reduction agreements