In the 1960s, the United States was an era of surging idealism and passion, and a large number of left-wing radical organizations emerged, of which "Students For Democratic Society for Democratic Society" (SDS) was the vanguard of anti-war, and the "the Weathermen" split from it was even more extreme among the radicals, blatantly brandishing the banner of overthrowing the US government, publicizing the action program of "bring the Vietnam War home", calling for violent revolution and smashing capitalism. The name "weatherman" comes from Bob Dylan's lyrics "you don't need a weatherman to understand the weather". Their typical action is a series of large-scale explosions that have been publicized beforehand, attacking objects directly at institutions and buildings that symbolize the US state apparatus, such as the Capitol, banks, oil consortia, FBI, and so on. Their core members are regarded as "terrorists". Although they have been wanted for many years, they have tried the law in invisibility for many years, and none of them has been caught, which is the most beautiful record of humiliating FBI in history. At the end of the Vietnam War in 1975, underground weather forecasters suddenly lost their way of action, and they were all over 30 years old, facing the pressure of life, family and employment.