What is the exposition of "The Destructors" by Graham Greene?

Exposition is generally the background information that
helps give the story a frame in which to be read and understood.  In the case of "The
Destructors" this frame can be attributed to the setting, the historical background and
the social situation of the young protagonists.

The story
is set in England, after WWII and as the Depression looms. It was a time of physical,
mental and financial recovery from a war with an unsettling, pessimistic view of the
future.

The boys in the story call themselves the Wormsley
gang and are reminiscent of the teddy boys from the era.  The teddy boys were packs of
juvenile deliquents who wreaked unexplained havoc where they went - thus the title of
the story. These boys frequent areas of town destroyed by bombs and look for ways to
pass the time and have fun with their devastation.

Their
target is a man's home.  Their senseless destruction and terrorization of the man and
his home are indicative of the attitudes of their generation and the harsh reality of
their world.