As for Europe, yes both World Wars had plenty of tragedy and somehow the survivors were not only able to carry on, they would get up the next day and fight. Russia probably had it the worst, first with the Bolsheviks carrying on their own terrorism. Later, the groups they suppressed carried out their own terrorism/freedom fighting.

In more recent times some terrible bombings have happened in Europe. None of the magnitude of last week, but whether it's one life, 100 or thousands, it still captures the hearts and minds of the nation attacked. Yet they do carry on.