The U.S. per capita ecological footprint
is 24 acres.
With a population of 300 million, total U.S. footprint is 7.2 billion acres,
about 3.6 times our physical land area.
China currently has a smaller per capita ecological footprint of 2 acres.
China's population of 1.3 billion yields a total Chinese footprint of 2.6 billion acres,
which also exceeds their available land.
Both countries have exceeded the biocapacity of their environment.
If everyone lived like an American, we would need more than 6 Earths to support the 7 billion individuals.