As we all know, CO2 is a natural part of life on Earth. We are made of carbon. The problem has been evidently laid out since the Industrial Age: we have put exorbitant and highly dangerous amounts into our atmosphere.
Burning fossil fuels. Rising atmospheric CO2 levels. Global warming. The 1-2-3 of climate change. As the GEICO ads say "everybody knows that!" But surveys suggest that, in fact, many people don't understand this simple relationship.
Keep this in mind if you are trying to contemplate how big a deal it is that some 350,000 people came out into the streets of Manhattan, the capital of capitalism, the cultural heart of the nation where manufactured denial has most stymied action.