SDS freshmen and sophomores in a lounge in Ferris Booth Hall. Known by the late 1960s primarily as a young theorist, publishing articles in New Left Notes and other movement publications, he went on to play an organizing role in the April–May 1968 Columbia student strike. On April 4, 1968, Gilbert was arrested for the first time, after joining a disturbance where 6 officers were engaged in a physical altercation with a protester. Gilbert's charge was assaulting a police officer. Gilbert maintained that the officer scraped his hand when he tried to hit Gilbert in the head with his baton. His lawyer advised him to take a plea bargain, and Gilbert pleaded guilty to disorderly conduct and was fined $50. During the Columbia strike, which began on April 23, 1968, Gilbert served as part of the strike team. Having good relations with some of the faculty, he was called on to be a negotiator. At the time of the strike he was still a graduate student at the New School for Social Research. In October 1969, he headed a Weather Underground collective in Denver and was arrested twice. The first arrest occurred while he was passing out leaflets in front of a community college and his comrades were inside setting off a smoke bomb. The second arrest led to a charge of "assault with a deadly weapon" after arresting officers found a rock in his pocket. Weather Underground In 1969, SDS split into different ideological factions and the Weathermen emerged, its purpose being to promote armed struggle among young white Americans in support of the Black Panthers and other militant groups, and also to oppose the war in Vietnam by means of activities intended to "Bring the War Home". Gilbert joined this group in 1969 with his friend Ted Gold, who later died in the March 1970 Greenwich Village townhouse explosion, along with fellow Weather members Diana Oughton and Terry Robbins. The group became clandestine, and the organization was renamed the Weather Underground. When Weather went underground, members often used money they already had or which they received from their family to fund their efforts. Gilbert cashed in his Israel bonds and half of that money went to supporting Weather and the other half was put into the Black Panther bail fund. Gilbert joined the Bay Area collective, living in a San Francisco apartment. He and another member were working