Why does Gatsby lose Daisy during the confrontation at the plaza? Could he have done anything to win her? If he could have, why doesn't he?

Gatsby tells Tom that Daisy doesn't love him, and has never loved him; he informs him that he's "not going to take care of Daisy anymore." Tom calls Gatsby a "common swindler" and reveals that he has made his fortune in bootlegging. Daisy, in her shallowness and snobbery, sides with Tom, and refuses Gatsby when he pleads with her to say that she has never loved her husband.

Tom uses the fact of Gatsby's criminal activity to humiliate him before Daisy. Tom, for all his crudeness, possesses a subtle knowledge of his wife: he realizes that Daisy's innate snobbery is ultimately identical with his own. She would never desert her aristocratic husband for "a common bootlegger," regardless of the love she felt for the bootlegger in question. Daisy refuses to submit to Gatsby's pleas, and will not say that she has never loved Tom. Gatsby is ultimately unable to recapture his idyllic past; the past, the future, and Daisy herself ultimately belong to Tom.