“Yes, the world is watching what we do. Yes, America's destiny is ours to choose. So let's be stronger together, my fellow Americans. Let’s look to the future with courage and confidence. Let’s build a better tomorrow for our beloved children and our beloved country. And when we do, America will be greater than ever.”

Presidential campaign (April 12, 2015 – 2016), Speech in (August 25, 2016)
Context: For all Americans. Because I believe we are stronger together. It’s a vision for the future rooted in our values and reflected in a rising generation of young people who are the most open, diverse, and connected we’ve ever seen.... Let’s keep moving forward together. Let’s stand up against prejudice and paranoia. Let’s prove once again, that America is great because is America is good.

2000s, A Challenge to Overcome (November 2007)

Games for Actors and non-Actors (1992)
Context: In truth the Theatre of the Oppressed has no end, because everything which happens in it must extend into life…. The Theatre of the Oppressed is located precisely on the frontier between fiction and reality – and this border must be crossed. If the show starts in fiction, its objective is to become integrated into reality, into life. Now in 1992, when so many certainties have become so many doubts, when so many dreams have withered on exposure to sunlight, and so many hopes have become as many deceptions – now that we are living through times and situations of great perplexity, full of doubts and uncertainties, now more than ever I believe it is time for a theatre which, at its best, will ask the right questions at the right times. Let us be democratic and ask our audiences to tell us their desires, and let us show them alternatives. Let us hope that one day – please, not too far in the future – we’ll be able to convince or force our governments, our leaders, to do the same; to ask their audiences – us – what they should do, so as to make this world a place to live and be happy in – yes, it is possible – rather than just a vast market in which we sell our goods and our souls. Let’s hope. Let’s work for it!

"In the long history of the world, only a few generations have been granted the role of defending freedom in its hour of maximum danger. I do not shrink from this responsibility — I welcome it." is one of seven quotes inscribed on the walls at the gravesite of John F. Kennedy at Arlington National Cemetery.
"The energy, the faith, the devotion which we bring to this endeavor will light our country and all who serve it — and the glow from that fire can truly light the world." is one of seven quotes inscribed on the walls at the gravesite of John F. Kennedy at Arlington National Cemetery.
"And so, my fellow Americans: ask not what your country can do for you — ask what you can do for your country. My fellow citizens of the world: ask not what America will do for you, but what together we can do for the freedom of man." is one of seven quotes inscribed on the walls at the gravesite of John F. Kennedy at Arlington National Cemetery.
It has been reported at various places on the internet that in JFK's Inaugural address, the famous line "Ask not what your country can do for you, ask what you can do for your country", was inspired by, or even a direct quotation of the famous and much esteemed writer and poet Khalil Gibran. Gibran in 1925 wrote in Arabic a line that has been translated as:
::Are you a politician asking what your country can do for you or a zealous one asking what you can do for your country?
::If you are the first, then you are a parasite; if the second, then you are an oasis in a desert.
However, this translation of Gibran is one that occurred over a decade after Kennedy's 1961 speech, appearing in A Third Treasury of Kahlil Gibran (1975) edited by Andrew Dib Sherfan, and the translator most likely drew upon Kennedy's famous words in expressing Gibran's prior ideas. For a further discussion regarding the quote see here.
1961, Inaugural Address
Context: In the long history of the world, only a few generations have been granted the role of defending freedom in its hour of maximum danger. I do not shrink from this responsibility — I welcome it. I do not believe that any of us would exchange places with any other people or any other generation. The energy, the faith, the devotion which we bring to this endeavor will light our country and all who serve it — and the glow from that fire can truly light the world.
And so, my fellow Americans: ask not what your country can do for you — ask what you can do for your country.
My fellow citizens of the world: ask not what America will do for you, but what together we can do for the freedom of man.

2010s, 2015, Speech on (20 July 2015)

In: Philosophy & Social Action (2003)

2014, Statement on Cuban policy (December 2014)

1980s, Second term of office (1985–1989), Farewell Address (1989)