well lets think about it, 4% (says Yahoo.com answers) of the carbon in the atmosphere are made from us using man made machines, but the rest of it is from the earth itself. now, b4 you start complaining i'm not done yet. the the ground has tons of carbon dioxide inside of it, in fact, farmers release tons (literally!) of carbon dioxide everyday just by plowing the field, so on top of man made machines comes our own use of nature which is the real killer of the earth.
but to be fare, taxing the higher up companies for the reasources they use should make sense
