Hendrik Hartog, a Princeton professor whose parents survived the Holocaust, said he learned from his parents that everyday life was a momentary accident likely to disappear.

All of us have read about, and some of us have experienced, a moment when ordinary living did disappear in the face of some unexpected tragedy or momentous event.

Families must cope after an attack by a terrorist or a deranged individual kills innocent loved ones. A tornado obliterates an entire town, leaving survivors to live without familiar symbols. Jews in 1930’s Germany faced a madman calling for the complete extermination of their race.

We assumed that the demise of the Soviet Union meant a world order leading ever upward toward democracy and civil society. Then angry young men from the Middle East intruded on a quiet September day in 2001 and upended that assumption.

Any person living long enough will experience unhappiness—the natural death of a loved one or loss of a job or a child making a wrong choice. What we do not expect is a gigantic break with the ordinary for large numbers of people.

How do those Syrians deal with it, those who became, in a short time, refugees taken from ordinary lives as shopkeepers and teachers and housewives?

How do any of us deal with the possibility that the ordinary can disappear for us, too?