ExxonMobil, the world's largest and most powerful oil company, knew everything there was to know about climate change by the mid-1980s, and then spent the next few decades systematically funding climate denial and lying about the state of the science....
But though we know now that behind the scenes Exxon understood precisely what was going on, in public they feigned ignorance or worse....
Thanks to Exxon's willingness to sucker the world, that world is now a chaotic mess.