The distortion of science for ideological purposes has a long history, and the results are generally ugly.
250,000 Geoscientists agree
2006 is the year of the planet and the IUGS has released a short handout "Earth and Life - origins and diversity" which includes the image below.
Note the rising increase in atmospheric oxygen and decreasing CO2 over geological time and that to make CO2, carbon has to bond with 2 oxygen atoms, so the plots of O2 and CO2 are interesting enough in themselves. (I expect the Adhominator and his mentor, Professor John Quiggin, will offer specious rebuttals).
Note that the mass species extinctions have no obvious relationship to CO2.Note that average global temperature has little correlation with CO2 content.
After all if 250,000 geoscientists concur.......
More information can be obtained here