Katowice, Poland (CNN)The American delegation came to promote coal. And the kids laughed in their faces. That was the bizarre and symbolic scene that unfolded Monday at the UN COP24 climate talks at a spaceship-shaped conference center in Polish coal country. The nations of the world are meeting here to hash out a "rulebook" to help ensure the viability of humanity -- preventing runaway global warming from causing even greater calamity in the form of superstorms, searing droughts and deadly heat waves. That work, which follows up on the 2015 Paris Agreement, is seen as more critical now than ever....