That is the question of the New Frontier. That is the choice our nation must make — a choice that lies not merely between two men or two parties, but between the public interest and private comfort — between national greatness and national decline — between the fresh air of progress and the stale, dank atmosphere of “normalcy” — between determined dedication and creeping mediocrity.
All mankind waits upon our decision. A whole world looks to see what we will do. We cannot fail their trust, we cannot fail to try.

John F. Kennedy (1917–1963) American politician, author, journalist, US President (1961–63)

Speech (1960-07-15), “The New Frontier,” Presidential Nomination Acceptance Speech, Democratic National Convention, Memorial Coliseum, Los Angeles
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(Source (Video)). In the the actual delivered speech, Kennedy says "... between dedication or mediocrity. All mankind waits upon our decision. A whole world looks to see what we shall do. And we cannot fail their trust, and we cannot fail to try."