"economic and political interests"
Or, while we're speculating, isn't it just as, if not more, likely that the denialist position is supported and promoted by economic and political interests which find the idea of possible economic controls and regulations anathema and will stop at nothing to put a stop to them? To me, this seems to be a much more reasonable assumption.
All of the sides have economic and political interests.
There are billions to be had in things like emission taxes (national and worldwide), international wealth transfers for emission control, cap-and-trade, and, at a much lower level, government and university research funds.
When you follow the money and power, do it across the board.