If your a psycho in the act of doing it is a differant question (please deposit one quarter for more responses :P ).
http://www.haganlaw.com/docs/Traitors.htm(snip)
ESPIONAGE: IT ISN’T EXACTLY TREASON, BUT YOU CAN STILL GET THE CHAIR
The Espionage Act was passed by Congress in 1917 in response to the first World War. Espionage is defined by statute as the act of spying or the gathering, transmitting or losing of information respecting the national defense with the intent or reason to believe that the information is to be used to the injury of the United States, or to the advantage of a foreign nation.
There are significant legal distinctions between spying and committing treason, although, at times, the offenses can merge. The only evidence that the prosecution needs to convict someone of violation of the Espionage Act is proof that the defendant:
(1) acted in such a way to incite sedition, riot, or revolution in America for the purpose of embarrassing and/or defeating the military plans of the government, or
(2) unlawfully uttered, printed, wrote or published, disloyal, scurrilous, and abusive language about the government of the United States intending to bring the government into contempt, scorn, contumely and disrepute.
Thus, it appears, that at least during war time, that the First Amendment of the United States may be suspended in the name of keeping America safe from espionage and sedition.
Espionage was rampant during the Civil War and employed by both the Union and Confederate Army. However, few were prosecuted for the sake of attempting to heal the wounds of the country. After World War I, America began in earnest to pursue and prosecute those who had disclosed her military plans and secrets to her enemies under the relatively new 1909 treason statute.
Undoubtedly, the most publicized and notorious case of espionage in this country’s history is that of Julius and Ethel Rosenberg in 1951. Prosecutors wanted to try the Rosenbergs for treason but understood they could not prevail due to the two-witness requirement. Therefore, the Rosenbergs, who were of Russian Jewish descent, were charged with and tried for espionage. Their offense was the delivery to the Russians of American know-how, methods and secrets concerning the atomic bomb which allowed the Russians to create nuclear weapons at least ten years before they would have otherwise been capable of making them.
The case was explosive and split the country into two camps. Those who believed the Rosenbergs were innocent and being unfairly prosecuted, and those who were afraid of the spread of Communism and nuclear annihilation. The Rosenberg case took place at the height of McCarthyism in this country. The Rosenberg saga started in February 1950, when Alger Hiss, also convicted of spying, informed authorities that he had passed secret information to a Communist agent named Whittaker Chambers. The investigation soon lead to the arrest of a man named Klaus Fuchs, who then confessed to disclosing to the Soviets information about the Manhattan Project. The Fuchs' arrest initiated a chain reaction of investigations whereby American cryptanalysts successfully deciphered intercepted cables (the "Venona Cables") from the Soviet Consulate to the KGB. One cable in particular lead authorities to a man named David Greenglass. Greenglass was a machinist-soldier stationed in Los Alamos, New Mexico, the military based where the United States conducted its top-secret atomic testing. Greenglass was the brother of Ethel Rosenberg.
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