Anti-nuclear poster from the 1970s American movement

Anti-nuclear poster from the 1970s American movement

On August 1st, 1976, the first nonviolent mass demonstration of the Clamshell Alliance took place at the proposed site of the Seabrook Nuclear Energy Facility in New Hampshire. The Clamshell Alliance was a group of anti-nuclear activists who worked to stop nuclear power plant construction at a time when President Nixon’s “Project Independence” had proposed the construction of over 1,000 nuclear power plants throughout the nation. Although the Clamshell Alliance was only partially successful in halting the Seabrook facility, their mass mobilizations deterred the plans for other plants and changed the landscape of nuclear energy forever. If not for the Clamshell Alliance, it is possible that we would be living in the nuclear nightmare of President Nixon’s vision of a thousand plants by the year 2000.

The Clamshell Alliance used a model of affinity groups of 6-20 people, and a spokes council system that functioned on consensus decision-making by all members. In July 1976, the Clamshell Alliance adopted a Declaration of Nuclear Resistance and by August 1st had mobilized their first protest of 200-600 people. Later in August, a second protest and civil disobedience action occupied the Seabrook construction site for 75 minutes, singing songs and planting trees. Nearly all of the 200 participants were arrested.

In April of 1977, the Clamshell Alliance mobilized 2,000 people for a demonstration. 1,400 participants were arrested, most refusing to post bail. They were held in jails and National Guard armories for up to two weeks. The activists used this time for training and networking, and subsequently, the detention of the activists was seen as a blunder on the part of Governor Meldrim Thomson.

In 1978, the Clamshell Alliance successfully organized another series of mass demonstrations and arrests. From June 23-26th, the alliance accepted an agreement to legally protest on the site for three days. Some sources claim this protest was one of the largest on-site protests in the history of the anti-nuclear movement, citing over 20,000 participants and very few arrests.

On March 29th, 1979, the meltdown of the Three Mile Island reactor in Harrisburg, Pennsylvania, propelled the dangers of nuclear power to the forefront of national concern. In collaboration with other groups, a huge anti-nuclear energy rally was organized in Washington, D.C. on May 6, 1979. Between 50,000 and 120,000 people gathered to protest nuclear power and demand safe alternatives.

These demonstrations played a major role in slowing and stopping the rush toward nuclear energy. Although Unit 1 of Seabrook Power Plant went online in 1990, Unit 2 was cancelled altogether. The project cost seven times the original billion-dollar estimate and was completed 14 years later than anticipated. In that time, hundreds of other proposals were dropped, due to the high social and fiscal costs encountered by the Seabrook Power Plant. For decades after the inception of the Clamshell Alliance and other similar groups, no new nuclear power facilities were proposed or constructed. The Clamshell Alliance left a lasting legacy in its organizing structure, movement practices, consensus model, and strategies for change. These are all tools and resources that can be used by current movements for change.



This article is from Rivera Sun’s book of nonviolent histories that have made our world. Click here for more information.


Rivera Sun is a change-maker, a cultural creative, a protest novelist, and an advocate for nonviolence and social justice. She’s a love-based revolutionary and the author of The Dandelion Insurrection, The Way Between and ten other fiction, non-fiction and poetry books. Her essays and writings are syndicated by Peace Voice, and have appeared in over a hundred journals nationwide. Rivera Sun speaks and facilitates workshops in strategy for nonviolent change across the country and around the world. She connects the dots between the issues, shares solutionary ideas, and inspires people to step up to the challenge of being a part of the story of change in our times.

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