“Public comments will be accepted as soon as the agency officially publishes the proposed rules.”
John Galt would send letters to the agency demanding that all companies be required to report their discharge of water vapor since water vapor us actually the most significant greenhouse gas. Soon, the Obama administration would be requiring restrictions on the release of water vapor. Then the capitalist system would collapse, and John Galt would take the credit.
Here's a comment on the significance of CO2:
The total concentration (all there is since the beginning of time) of CO2 in the atmosphere is ~360 parts per million (ppm).
How big is 360 ppm?