The correct answer to this open question is the following.
The phrase of Edward Bernays that contributed to the Versailles Peace Treaty was that he convinced his counterparts that the Versailles Peace Treaty would help to bring peace and democracy to Europe.
That experience led to his idea for a new peacetime company, he labeled this new field called Propaganda and later, Public Relations.
He did choose that language because he found that if you were able to appeal to the subconscious mind of people, you could convey the kinds of messages you want them to believe.
That is what he did when he was hired as part of the Committee of Public Information (CPI) during World War I, helping the Woodrow Wilson administration to adapt the proper messages to keep American citizens informed.
