There are many "D days" and "H hours" in a war. Set against some vast and seemingly cosmic clock, these innocuous letters--so insignificant in their apparent power--announce the precise day and exact hour when desperate men will be caught up in a deadly drama.

Later, when war's dreadful vocation is complete, some will come home to final resting places immaculately maintained while others--perhaps less fortunate--will find themselves in a veterans' administration hospital to recuperate, to heal their physical and emotional scars, and, once again, to make some small claim on life. Such...