The historic presidential yacht Sequoia, built in 1925 and in a sad state of disrepair, is heading up to Maine for a complete restoration. It then will be displayed on the Washington, D.C., waterfront where it will be used to teach about American history and promote ocean conservation. The Sequoia served eight presidents, starting with Herbert Hoover, until Jimmy Carter put it up for auction in 1977. FDR, a former assistant secretary of the navy, used it to host foreign dignitaries. JFK, who commanded a PT boat in the Second World War, added a king-sized bed and celebrated his 46th…