“I am at heart more of a United-States-man than an Englishman.”

Letter to the Reverend G. W. Snyder (24 October 1798) http://etext.virginia.edu/etcbin/toccer-new2?id=WasFi36.xml&images=images/modeng&data=/texts/english/modeng/parsed&tag=public&part=388&division=div1
1790s
Context: !-- Revd Sir I have your favor of the 17th instant before me; and my only motive to trouble you with the receipt of this letter, is to explain, and correct a mistake which I perceive the hurry in which I am obliged, often, to write letters, have led you into.
--> It was not my intention to doubt that, the Doctrines of the Illuminati, and principles of Jacobinism had not spread in the United States. On the contrary, no one is more truly satisfied of this fact than I am.
The idea that I meant to convey, was, that I did not believe that the Lodges of Free Masons in this Country had, as Societies, endeavoured to propagate the diabolical tenets of the first, or pernicious principles of the latter (if they are susceptible of seperation). That Individuals of them may have done it, or that the founder, or instrument employed to found, the Democratic Societies in the United States, may have had these objects; and actually had a seperation of the People from their Government in view, is too evident to be questioned. <!--
My occupations are such, that but little leisure is allowed me to read News Papers, or Books of any kind; the reading of letters, and preparing answers, absorb much of my time. With respect — I remain Revd Sir Your Most Obedt Hble Ser. Go: Washington

A statement he is reported to have made several times to others after the secession of South Carolina, or as early as after the election of Abraham Lincoln (1860), as quoted in Lincoln's War: The Untold Story of America's Greatest President as Commander in Chief (2004) by Geoffrey Perret.

2016, DNC Address (July 2016)
Context: You know, nothing truly prepares you for the demands of the Oval Office. You can read about it. You can study it. But until you’ve sat at that desk, you don’t know what it’s like to manage a global crisis, or send young people to war. But Hillary has been in the room; she’s been part of those decisions. She knows what’s at stake in the decisions our government makes — what’s at stake for the working family, for the senior citizen, or the small business owner, for the soldier, for the veteran. And even in the midst of crisis, she listens to people, and she keeps her cool, and she treats everybody with respect. And no matter how daunting the odds, no matter how much people try to knock her down, she never, ever quits.
That is the Hillary I know. That’s the Hillary I’ve come to admire. And that’s why I can say with confidence there has never been a man or a woman — not me, not Bill, nobody — more qualified than Hillary Clinton to serve as president of the United States of America.

Quoted in Chicano Power: The Emergence of Mexican America by Tony Castro, ISBN 0841503214.

This I Believe (1952)
Context: I believe in —  I am proud to belong to —  the United States. Despite shortcomings, from lynchings to bad faith in high places, our nation has had the most decent and kindly internal practices and foreign policies to be found anywhere in history.
And finally, I believe in my whole race. Yellow, white, black, red, brown — in the honesty, courage, intelligence, durability … and goodness …. of the overwhelming majority of my brothers and sisters everywhere on this planet. I am proud to be a human being. I believe that we have come this far by the skin of our teeth, that we always make it just by the skin of our teeth — but that we will always make it … survive … endure. I believe that this hairless embryo with the aching, oversize brain case and the opposable thumb, this animal barely up from the apes, will endure — will endure longer than his home planet, will spread out to the other planets, to the stars, and beyond, carrying with him his honesty, his insatiable curiosity, his unlimited courage — and his noble essential decency.
This I believe with all my heart.

Source: 1880s, Incidents and Anecdotes of the Civil War (1885), pp. 34&ndash; 35

2000s, Farewell address (18 January 2001)

Part 4, Chapter 8 (p. 61)
Fiction, The Female Man (1975)

Source: The Old Man and the Sea (1952)