I would say that Salinger's work was one of the first works of art to critically assess the shortcomings in post World War II American life. If we go back and examine where America was at the time, the term "zenith" would be appropriate. Essentially, the world looked to America as the nation that "had it all." Europe was decimated by two protracted wars financially, socially, and politically. Nations in Asia, Africa, and South America were just beginning to establish their own independence. The Soviet Union was closed off to the rest of the world as the Iron Curtain descended. America was seen as "perfect" in many ways. To a large extent, its citizens started believing this, as well. In this light, there was much in way of delusion being developed. Works like "The Catcher in the Rye" helped to bring to light that there might be something subterranean that explores elements that are wrong in and with American society. The idea of "phonies" and individuals who do one thing and say another could be quite appropriately to a culture that might have professed its belief in independence, justice and equality of opportunity, yet openly denied it to people of color and women in the time period. The idea that there was an "established" way to behave belied the American notion of change and democratic horizons. When Holden speaks of a world that might not fulfill what is promises and speaks of a desire to protect innocence from the corruption, he is laying the groundwork for the swelling of transformative social change that emerges in the 1960s. In this light, the book helped give a voice to what can be as opposed to what is.
At the time of Catcher being published, the nation was entranced by the new prosperity following the end of WWII and the increase in consumerism and the rising living standards around most of the country helped fuel conservatism and a sincere desire to look to this new exciting future rather than looking back at the horrors of the war.
In this atmosphere, people were not really interested in hearing about a somewhat crazy teenager dealing with prostitutes and profanity and sex and the book served to bring up this topic effectively and in a timely way. Many communities actually banned the book because it was considered so shocking, but it helped to open the door for further stories like it.