Wow. Now I have heard of this stuff, but like most Americans am clueless as to what it really was--this also is from Wikipedia:
The Weather Underground Organization (WUO), commonly known as the Weather Underground, was an American radical left organization founded on the Ann Arbor campus of the University of Michigan.
Originally called Weatherman, the group became known colloquially as the Weathermen. Weatherman organized in 1969 as a faction of Students for a Democratic Society (SDS) composed for the most part of the national office leadership of SDS and their supporters.
Their goal was to create a clandestine revolutionary party for the overthrow of the U.S. government. With revolutionary positions characterized by Black power and opposition to the Vietnam War, the group conducted a campaign of bombings through the mid-1970s and took part in actions such as the jailbreak of Dr. Timothy Leary. The "Days of Rage," their first public demonstration on October 8, 1969, was a riot in Chicago timed to coincide with the trial of the Chicago Seven. In 1970, the group issued a "Declaration of a State of War" against the United States government, under the name "Weather Underground Organization".
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