Donald Trump says it’s a scam to say that climate change is a threat to public health. So, the US president has killed off a scientific finding that says it is.The so-called endangerment finding was the basis for nearly all climate laws in the US.Now it’s gone, the White House hopes dirty industries can flourish again, including America’s petrol car manufacturers. Today, ANU climate expert, Christian Downie on what happens when one of the world’s largest polluters gives up on reducing greenhouse gas emissions. Featured: Christian Downie, professor in the school of regulation and global governance at the Australian National University