What is the central idea of "Guests of the Nation?"

The central idea of O'Connor's work is that "in war,
hatred and revenge drive out ethical and moral intelligence.’’  This condition is
brought out in the ending.  After befriending the British soldiers, the Irish soldiers
are forced to adhere to a code of duty that seems to deny personal choice and voice.
Bonaparte and Noble participate in "monstrous acts of evil" under the code and cover of
duty.  

The central idea of the story is this aspect.  War
brings out the worst in humanity.  It is not one in which there an be any clear winners.
 The British soldiers lose because they are to be killed in the name of partisanship.
 The Irish soldiers end up losing, as well, for their moral character cannot be cleaned
of the stench attached to what they did.  It is for this reason that Noble falls to his
knees in prayer at the end, almost begging forgiveness which he knows he will never
receive.  Bonaparte becomes emotionally distant as a result of what he has done.  The
central idea in this ending is that war generates a condition in which there is only
loss and nothing in terms of "victory" is evident.