Propaganda has been mostly used in two situations: wartime and public relations.
Propaganda is a mighty weapon in times of war. In this case its aim is usually to dehumanize and create hatred toward a supposed enemy, either internal or external. The technique is to create a false image in the mind. This can be done by using special words, special avoidance of words, or by saying that the enemy is responsible for certain things he never did. Most propaganda wars require the home population to feel the enemy has inflicted an injustice, which may be fictitious or may be based on facts. The home population must also decide that the cause of their nation is just.
During World War I, Lippman and Bernays were hired by then United States president, Woodrow Wilson, to participate in the “Creel Commission,” the mission of which was to sway popular opinion in favor of entering the war on the side of the United Kingdom. The Creel Commission provided themes for speeches by "four-minute men" at public functions, and also encouraged censorship of the American press. The commission was so unpopular that after the war, Congress closed it down without providing funding to organize and archive its papers.
The war propaganda campaign of Lippman and Bernays produced within six months such an intense anti-German hysteria as to permanently impress American business (and Adolf Hitler, among others) with the potential of large-scale propaganda to control public opinion.
The public relations industry is a direct outgrowth of Lippman's and Bernays' work and is still used extensively by the United States government. For the first half of the twentieth century, Bernays and Lippman ran a very successful public relations firm.