They considered the commercial world to be the essence of corruption. The goal of the Socialist party in The Jungle was to end the corrupt and powerful Beef Trust. After reading The Jungle, a person would never expect the United States to survive as a Capitalist country. The only option shown to the reader is Socialism. The author never mentions the good that Capitalism has done, nor does he mention any possible flaws in Socialism.
Socialism is presented as perfection, while all other philosophies are flawed.
The promotion of Socialism is understandable, though, since Sinclair himself was a Socialist from an early age. He was brought up in a poor and not very successful family. This could explain why he became a Socialist, since one of the main ideals of Socialism is equality for everyone. The Jungle is, however, more than an advertisement for Socialism. It describes the horrors of the meat packing industry in great detail.