It’s human nature. No one wants to hear bad news. Doom-sayers are especially suspect. How many times has the prophesized end of the world failed to arrive? And then there is the seductive power of denial. There is good reason Al Gore’s Academy Award winning documentary about global climate change was called “An Inconvenient Truth.” And, oh yes, politics—if progressives claim something is true, it must, on ideological principle, be false. Finally, there is the nature of time itself: It will happen when? In the as yet uncertain future?