Historian David Greenberg, writing for Slate, explains the origins and early uses of the Espionage Act of 1917, a law that some hope to use to prosecute WikiLeaks founder Julian Assange. Greenberg writes that there was a real threat of spying and sabotage, as evidenced by a briefcase confiscated by Secret Service agents following “German propagandist” George Sylvester Viereck:
The documents that Wilson and McAdoo beheld detailed a sweeping secret campaign, linked to high-ranking German officials, of espionage, sabotage, and propaganda. There were plans to take over American newspapers, bankroll films, send hired lecturers on the Chautauqua circuit, and create pseudo-indigenous movements to agitate on behalf of pro-German policies. More disturbing were schemes to provoke strikes in armaments factories; to corner the supply of liquid chlorine, an ingredient in poison gas, in order to keep it from Allied hands; even to acquire the Wright Brothers’ Aeroplane Company and use its patents on Germany’s behalf. American officials also learned of sabotage plans hatched by a different German spy, Franz Rintelen von Kleist, who was plotting to destroy American munitions plants and blow up the Welland Canal, a Canadian waterway of vital importance to the United States. It was no wonder that Wilson wrote to his adviser Edward House that summer that the country was “honeycombed with German intrigue and infested with German spies.”
World War I seems to have been the first war that used modern propaganda techniques, and of course the Germans were hardly alone in their desire to sway American opinion. The British were quite successful in their portrayal of the Germans as the barbarians who raped Belgium. I would surprised if other countries besides Germany didn’t have plans that had some things in common with German plans. Still, those plots are pretty striking, even though I doubt that they all could have been carried out.
Greenberg also looks at the abuses of the act during World War I:
The resulting crackdown on antiwar groups under the Espionage Act—and the shame it brought to Wilson and the nation—is widely known. Postmaster General Albert Burleson, a reactionary and intolerant Texan considered by Edward House to be “the most belligerent member of the cabinet,” denied use of the mails to publications like the left-wing Masses and scared many others into silence. Around the country, meanwhile, the U.S. attorneys in Thomas Gregory’s Justice Department prosecuted socialists, pacifists, and German-Americans on flimsy grounds. Many people were arrested for crimes of mere speech. Filmmaker Robert Goldstein was prosecuted for making a movie about the American Revolution that depicted the British—now a U.S. ally—in an unfavorable light. The socialist leader Eugene Debs was thrown in jail for a speech that defended freedom of speech. Of 1,500 arrests under the law, only 10 involved actual sabotage. To the dismay of progressives, moreover, not even the Supreme Court stopped the prosecutions. In March 1919, the liberal icon Oliver Wendell Holmes, coining his famous “clear and present danger” standard, led the court in upholding three dubious Espionage Act verdicts, including the conviction of Debs.