All states have secretive or secret bodies performing certain functions: foreign intelligence and espionage, security at home, military research, and possibly other things they don't want the public to find out about. Some have large public headquarters and are regulated by statute; others may be "skunkworks" projects or secret programs in bigger organisations. Because these programs are often secret or their operations are deliberately kept from public knowledge, a vast body of conspiracy theory, rumors, and occasionally outright lies, build up around them. This article lists the real, possibly real, and almost certainly fictitious secret bodies through over 200 years of American history.
War of Independence
First World War and anarchist menace
World War Two
United Nations/new world order