On Monday, the Supreme Court refused to take up the appeal lodged by environmental groups that focused on a two-mile stretch of border fence in the San Pedro Riparian National Conservation Area near Naco, Ariz. The fence, which has been built since the petition was filed, is a vital part of the Bush administration’s drive to secure the border between the United States and Mexico. The Supreme Court’s decision is a welcome and needed victory in the war against illegal immigration and efforts to preserve the unique character that is America. The environmentalists based part of their challenge on claims...