for totalitarianism." The clause's removal effectively invited "disciplined cadre" to attempt to "take over or paralyze" SDS as had occurred to mass organizations in the thirties. Afterwards, Marxism–Leninism, particularly the PLP, helped to write "the death sentence" for SDS, which nonetheless had over 100 thousand members at its peak. Monopoly Capital: An Essay on the American Economic and Social Order is a book by Paul Sweezy and Paul A. Baran published in 1966 by Monthly Review Press. It made a major contribution to Marxian theory by shifting attention from the assumption of a competitive economy to the monopolistic economy associated with the giant corporations that dominate the modern accumulation process. Their work played a leading role in the intellectual development of the New Left in the 1960s and 1970s. As a review in the American Economic Review stated, it represented "the first serious attempt to extend Marx's model of competitive capitalism to the new conditions of monopoly capitalism." It has recently attracted renewed attention following the Great Recession. In the 1960s, the hippie movement influenced a renewed interest in anarchism, and some anarchist and other left-wing groups developed out of the New Left and anarchists actively participated in the late sixties students and workers revolts. Anarchists began using direct action, organizing through affinity groups during anti-nuclear campaigns in the 1970s. The New Left in the United States also included anarchist, countercultural and hippie-related radical groups such as the Yippies who were led by Abbie Hoffman, the Diggers and Black Mask/Up Against the Wall Motherfuckers. By late 1966, the Diggers opened free stores which simply gave away their stock, provided free food, distributed free drugs, gave away money, organized free music concerts and performed works of political art. The Diggers took their name from the original English Diggers led by Gerrard Winstanley and sought to create a mini-society free of money and capitalism. On the other hand, the Yippies employed theatrical gestures, such as advancing a pig ("Pigasus the Immortal") as a candidate for president in 1968, to mock the social status quo. They have been described as a highly theatrical, anti-authoritarian and anarchist youth movement of "symbolic politics." Since they were well known for street theater and politically themed pranks, many of the "old school" political left either ignored or denounced them. According to ABC News: "The group was known for street theater pranks and was once referred to as