The Walter Isaacson interview with Trump appointee Daniel Yergin last week was troubling. Mr. Yergin promoted extraction and use of fossil fuels, including fracking, into an indefinite future and attempted to undermine future claims of damage to the planet. Mr. Isaacson made little attempt to hold Yergin to a more factual representation or substantiate his views. It is more troubling when this happens at PBS, and it is happening more often.