In September 1970, at a conference in Seattle, Washington, U.S. Senator Gaylord Nelson of Wisconsin announced that in the spring of 1970 there would be a nationwide grassroots demonstration on the environment. Senator Nelson first proposed the nationwide environmental protest to thrust the environment onto the national agenda. "It was a gamble," he recalls, "but it worked." Each year, the April 22 Earth Day marks the anniversary of the birth of the modern environmental movement in 1970. Earth Day is the only event celebrated simultaneously around the globe by people of all backgrounds,...