A century ago, World War I--the war to end all wars--brought death and destruction literally and figuratively on an industrial scale throughout Europe, and parts of Asia, the Middle East, Africa, China, and off the coasts of North and South America.
Very few soldiers were immune to the psychological wounds of war. The term "Shell Shock" was added to the lexicon of war, which defined how servicemen reacted under the heavy barrage of artillery, poison gas, and angst of "going over the top" (climbing out of the trenches) to certain death.
Whether it was defined as Shell Shock a century ago or today's PTSD, soldiers and civilians (who have endured traumatic events) have a breaking point, but it's compounded especially in the theater of war.
World War One shell shock film: https://www.youtube.com/watch?v=nsSkL3Yl0rA (VIEWER DISCRETION IS ADVISED)
Follow this link for more information about Shell Shock and PTSD: http://www.fairobserver.com/region/north_america/psychological-wounds-of-conflict-the-impact-of-world-war-one-71084/