Hitler himself, in Mein Kampf, laid down his rules for dictatorship. He stated the “principle of the whopping lie” and of the gullibility of the masses. If you are going to tell a lie, he said, and nobody doubts that he intended to, don’t tell a little one, because it will be recognized as a lie. Tell the biggest and most unlikely lie you can think of, keep on telling it, and the people will think it must be the truth and believe it. “The greater the lie, the more effective it is as a weapon,” said the master of the alleged “master race.”

Moreover, he went on, don’t be fooled into thinking that you have to sway the influential people—the leaders of opinion—to your side first. “Toward whom must propaganda be directed,” he asked, “toward the scientific intelligentsia or toward the uneducated masses?” His answer was, “It must always and exclusively be directed toward the masses. The teachability of the great masses is very limited, their understanding small, and their memory short.” In a word, he believes that it pays to take advantage of ignorance and that it is therefore best to keep the people ignorant.

Democracy is a different kind of system from the ground up. It is based on the people, and it works well in proportion as the people are enlightened and informed about what goes on both in peace and in war (though of course democratic people recognize the wisdom of some wartime censorship imposed for security reasons). This basic democratic principle was stated by President George Washington in his Farewell Address when he said, “In proportion as the structure of a government gives force to public opinion, it is essential that public opinion should he enlightened.” To the degree that people are denied access to the facts and to a wide range of independent interpretations of the facts, democracy fails to function effectively.

These simple truths determine the underlying or governing principles of democratic propaganda. The Nazis blindfold their people against the truth. In exact opposition to the rules of Hitler, the democratic countries must present the truth in their propaganda. A free people will soon find out the truth in spite of official suppressions and distortions. And when propaganda has been revealed to be deceitful and distorted, it no longer is effective. Moreover, democratic propaganda must observe the right of the people to know the facts, however unpleasant they may be. The strategy of truth is not only in accord with the basic principles of democracy, but is also a hardheaded and realistic policy for effective dealing with allies, neutrals, and even enemies.

From EM 2: What Is Propaganda? (1944)