In the 19th century the US image was tied in with the worldwide dream of striking gold. In the 20th century the image was one of an ethnic melting pot for immigrants coming from around the world. In the 21st century the image is that of an unchallenged political, economic and military superpower. American-style cultural icons like Hollywood, McDonald's and Microsoft have conquered the world through their creativity and vitality.
19 世紀的美國牽繫著全球淘金夢，20 世紀成為全球移民嚮往的民族熔爐，21 世紀則是無可挑戰的政經與軍事超級強權；而美式文化如好萊塢、麥當勞與微軟科技等，更以創意和活力征服全球。