As Brazilian author Paulo Coelho writes, “You drown not by falling into a river but by staying submerged in it.” This is an apt metaphor for how trauma impacts people, individually and collectively.

Much has been said about rises in mental health problems reported by younger people over the past 20 years. It is estimated that the prevalence of anxiety for 18-to-25-year-olds was about 8% in 2008, ...