and it came from the highest disgraced office in our land.
To avoid the abuses of the English law (including executions by Henry VIII of those who criticized his repeated marriages), treason was specifically defined in the United States Constitution, the only crime so defined. Article Three defines treason as only levying war against the United States or "in adhering to their Enemies, giving them Aid and Comfort," and requires the testimony of two witnesses to the same overt act or a confession in open court for conviction. This safeguard may not be foolproof since Congress could pass a statute creating treason-like offences with different names (such as sedition, bearing arms against the state, etc.) which do not require the testimony of two witnesses, and have a much wider definition than Article Three treason. For example, some well-known spies have generally been convicted of espionage rather than treason. In the United States Code the penalty ranges from "shall suffer death" to "shall be imprisoned not less than five years and fined under this title but not less than $10,000; and shall be incapable of holding any office under the United States."
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Several people generally thought of as traitors in the United States, such as the Walker Family, or Julius and Ethel Rosenberg, were not prosecuted for treason per se, but rather for espionage. John Walker Lindh, the "American Taliban" fighter in Afghanistan, was also thought of as a traitor by many. However, instead of being tried for treason, he pleaded guilty to conspiracy to murder US nationals, aiding the Taliban and terrorist offences relating to Al Qaeda, even though he joined the Taliban before September 11, 2001, in the period when the Bush administration was aiding the Taliban to help their destruction of the opium crop.
Treason has become largely a wartime phenomenon in the 20th century, and the treason cases of World Wars One and Two were of minor significance. Most states have provisions in their constitutions or statutes similar to those in the U.S. Constitution. There have been only two successful prosecutions for treason on the state level, that of Thomas Dorr in Rhode Island and that of John Brown in Virginia.
In 1964, an author named John A. Stormer wrote a book considered a backstairs political classic and titled it None Dare Call It Treason—the book unexpectedly sold seven million copies with little or no advertising. It was revised and reissued by the original author in 1990. The title phrase comes from a 17th-century epigram by John Harington: "Treason doth never prosper: what's the reason?/For if it prosper, none dare call it treason." This phrase refers to treason defined as attempting to overthrow the government. Since its popularization by Stormer, it has been reused and paraphrased many times and has become part of popular culture.
http://en.wikipedia.org/wiki/Treason#United_States