Are We Scaring Ourselves to Death?

-In the last twenty years, incidents of crime have declined by 25 percent. -Automobiles of today emit just 1 percent of the pollution that spewed from cars of the 1970s. -The national recycling rate is about 22 percent-seven times the rate of only ten years ago. -The average human life span continues to increase. Given all of these positive trends, why do so many people envision a bleak future for the world? More to the point, why are so many people scaring themselves to death? In this lively an