The Importance of Effective Writing

It's truly amazing what the written word is capable of.  It can create a clear picture of a person, scene, landscape, and so on, in a way that transports a reader to those places.  But it needs to be well written. 
Recently I took out an old textbook from an English course I had to take for my nursing degree and came across an introduction that reads like a spy novel, only it was real life.  Taken from the Sundance Reader, it reads in part

"In the summer of 1939 scientist Leo Szilard was worried.  .  . the exiled physicist followed events in Europe with growing anxiety.  His experiments proved that a nuclear chain reaction could create an atomic bomb.  German scientists had split the atom, and the Nazis had seized rich deposits of uranium in Czechoslovakia.  As a Jew who had escaped on the last train out of Nazi Germany, Szilard was horrified at the prospect of Hitler obtaining nuclear weapons."  He tried to warn the American government but was getting nowhere, so he sought help from his friend Albert Einstein.  "Although the idea of a nuclear chain reaction had never occurred to him, Einstein quickly grasped its implications and suggested writing President Roosevelt."  With a third scientist involved, the three set about trying to write the president explaining the danger, but they struggled with it, writing several versions.  They were frustrated because of the abstract theories they had to explain and English was for all three a second language.

The first paragraph of the actual letter sends a chill down my spine, it reads in part:  "...uranium may be turned into a new and important source of energy in the immediate future.  Certain aspects of the situation which has arisen seem to call for watchfulness and, if necessary, quick action on the part of the Administration.  I believe therefore that it is my duty to bring to your attention the following facts . . "

Just thought I'd share this.  The point that the book was making was on the importance of conveying an idea to your reader in a way that will make it clear for them.  A reader comes from a different background, and if the author doesn't take that into account, the story will be lost.