That's a tough one... most everyone outside the US has long been convinced that global warming is not only is happening and caused by us, but that we all must start making the changes needed to avert the worst of it in the near future. In the US, thanks to political marketing groups funded heavily by the oil & gas and coal industries (and
others), like the pathetic Heartland Institute that was recently in the news, the false appearance of a debate (in only the US) persists. It will take the concerted effort by the people, media and strong leaders to accept the truth and start the actions that are seriously needed now. The "debate" has been over for at least a decade... and we are only embarrassing ourselves and putting everyone on the planet at risk the longer we allow the issue to remain a political joke in the US. A couple of sites I recommend for further info and ways to get involved today are:
CO2Now
http://co2now.org/and
350.org
http://www.350.org/