The threat of cataclysmic climate change on earth is far greater from an asteroid impact than from carbon dioxide emissions. That is obvious when one considers that many asteroid impacts have occurred in the past, with devastating results, while an order of magnitude higher atmospheric carbon dioxide levels did little to temperature. About 13,000 years ago an asteroid exploded over North America and destroyed most of the continent. In 1908 a small asteroid exploded over Siberia and wiped out hundreds of square miles. Here is an article on the asteroid threat. Of course politicians are more interested in carbon dioxide emissions since controlling that gives them more power. They can't get much additional power by trying to prepare for a threatening asteroid, so they ignore that threat.