Many U.S. troops who fired vast numbers of artillery rounds against the Islamic State developed mysterious, life-shattering mental and physical problems. But the military struggled to understand what was wrong.
Travelers who use their off time to visit places like the Chernobyl nuclear plant or current conflict zones say they no longer want a sanitized version of a troubled world.
Many Americans believe that their home is inhabited by ghosts, a conviction that researchers attribute to the rise of paranormal-related media, a decline in religious beliefs and the pandemic.