I'm not sure what point you are making. There is clearly no deficit of C02 in the atmosphere in the foreseeable future - it is rising at about 2 ppm annually (about 2/3%). As for the old "CO2 is plant food" argument, it is true that increased CO2 does increase plant growth but the whole story is not that simple. What is good for plants may not necessarily be good for humans or the rest of the ecosystem. Increased CO2 leads to significant reduction in the protein content of important food crops and increased toxins in many plants. The ABC science program Catalyst has an interesting piece that is worth a look: http://www.abc.net.au/catalyst/stories/2891924.htm
my point is ... that whatever the cause, life flourishes in warmth and truth dies in propaganda laced bullshit (you previously questioned the significance of Al Gore, do you realize that a student in a Texas high school will have been forced to watch his horror film between 2-4 times before graduation?)