“Fellow citizens: The year ahead will demand more patience, sacrifice, and resolve. It can be tempting to think that America can put aside the burdens of freedom. Yet times of testing reveal the character of a nation. And throughout our history, Americans have always defied the pessimists and seen our faith in freedom redeemed. Now America is engaged in a new struggle that will set the course for a new century. We can, and we will, prevail.”

2000s, 2001, First inaugural address (January 2001)
Context: Together, we will reclaim America’s schools, before ignorance and apathy claim more young lives. We will reform Social Security and Medicare, sparing our children from struggles we have the power to prevent. And we will reduce taxes, to recover the momentum of our economy and reward the effort and enterprise of working Americans. We will build our defenses beyond challenge, lest weakness invite challenge. We will confront weapons of mass destruction, so that a new century is spared new horrors. The enemies of liberty and our country should make no mistake: America remains engaged in the world by history and by choice, shaping a balance of power that favors freedom. We will defend our allies and our interests. We will show purpose without arrogance. We will meet aggression and bad faith with resolve and strength. And to all nations, we will speak for the values that gave our nation birth.

2000s, 2001, First inaugural address (January 2001)

2000s, 2001, Freedom and Democracy Are Under Attack (September 2001)
Context: I want to thank the members of Congress for their unity and support. America is united. The freedom-loving nations of the world stand by our side. This will be a monumental struggle of good versus evil. But good will prevail.

"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.

2000s, 2003, Invasion of Iraq (March 2003)

President Bush Visits Mount Vernon, Honors President Washington's 275th Birthday on President's Day http://georgewbush-whitehouse.archives.gov/news/releases/2007/02/20070219.html (February 19, 2007)
2000s, 2007

2014, Young Southeast Asian Leaders Initiative Town Hall Speech (November 2014)

2000s, 2002, Compassionate Conservatism (April 2002)

2000s, 2005, Address to the National Endowment for Democracy (October 2005)