Sometimes the article “ The ” is used as part of the name of a company or magazine or journal for emphasis, ., The Champ , or The Sports Network . For Internet sites, use the URL as a guide. If “ theyellowpages ” is used in the URL, treat “ The ” as part of the title, and list “ The Yellow Pages ” alphabetically under “ The “. If “ edge ” and not “ theedge ” is used in the URL, list the magazine title “ The Edge ” under “ Edge ” and treat “ The ” as an article and ignore it.
It might help to think of "greatness" in terms of being 'large' or 'of magnitude' rather than being 'good' or 'worthy of admiration.' Sometimes a really terrible person can be 'great' in this sense, because they accomplish things larger than life. The novel is about the vacuousness and emptiness at the heart of the American dream that everyone struggles so desperately to achieve. Gatsby is, as you note, the epitome of the 'American ideal'. He represents the desires of his culture the way few can. He has climbed from the gutter to the penthouse, a la Horatio Alger, and literally reinvented who he is. He is rich, too. Talk about greatness in terms of how he represents the American dream. On the other hand, the title is certainly ironic. Everyone is eventually let down by regarding Gatsby as great. At heart, he remains the scared kid who changed his name, and the tragedy is that the truth always comes back. His old poor dad is always hiding in the wings ... he might change his name but he's still just navigating his life as we all are. So Nick and Daisy are ultimately led into a sad tragedy by hoping that the 'greatness' of Gatsby will shine on them.