that seems clear enough

This strange state of affairs may be rooted in human psychology. As the Harvard psychologist Daniel Gilbert put it in a 2006 op-ed article in The Los Angeles Times, “Global warming is bad, but it doesn’t make us feel nauseated or angry or disgraced, and thus we don’t feel compelled to rail against it as we do against other momentous threats to our species, such as flag burning.”

People tend to have strong emotions about topics like food and sex, and to create their own moral rules around these emotions, he says. “Moral emotions are the brain’s call to action,” he wrote. “If climate change were caused by gay sex, or by the practice of eating kittens, millions of protesters would be massing in the streets.”
New York Times, 20/2/10