The concentration of greenhouse gases in the atmosphere has been dramatically rising for the past 150 years. This fact and the possible link between GHG concentration and rising temperature of the Earth caused that the reduction of greenhouse gases has recently emerged as widely discussed issue.
First step to cut CO2 emissions is to identify countries with the highest contribution to the worldwide emissions. From this point of view the emissions of China and USA are very similar.
However the information about absolute CO2 emissions per country is not fully correct for most of comparisons. Much better is to compare CO2 emissions per capita. From this point of view, which comes from idea that every people have the same right to consume the natural resources and produce waste, the emissions of China are much lower than that of the USA.
Information about CO2 emissions is relatively simple indicator. There are more complex indicators that should be used in case of sustainable development assessment.