The term 'From Sea to Shining Sea' is a phrase from the American national anthem, 'The Star-Spangled Banner'. It refers to the vast expanse of the United States, from the Atlantic Ocean to the Pacific Ocean. The two crossword solutions, COUNTRYWIDE (11 letters) and NATIONWIDE (10 letters), are related to this phrase as they both refer to something that is spread across the entire country. COUNTRYWIDE means 'throughout the country' while NATIONWIDE means 'throughout the nation'.