“Offensive realism predicts that the United States will send its army across the Atlantic when there is a potential hegemon in Europe that the local great powers cannot contain by themselves.”

Report on Manufactures (1791)
Context: If the system of perfect liberty to industry and commerce were the prevailing system of nations, the arguments which dissuade a country in the predicament of the United States, from the zealous pursuits of manufactures would doubtless have great force. (...) But the system which has been mentioned, is far from characterising the general policy of Nations. The prevalent one has been regulated by an opposite spirit. The consequence of it is, that the United States are to a certain extent in the situation of a country precluded from foreign Commerce. They can indeed, without difficulty obtain from abroad the manufactured supplies, of which they are in want; but they experience numerous and very injurious impediments to the emission and vent of their own commodities. (...) In such a position of things, the United States cannot exchange with Europe on equal terms, and the want of reciprocity would render them the victim of a system, which should induce them to confine their views to Agriculture and refrain from Manufactures. A constant and increasing necessity, on their part, for the commodities of Europe, and only a partial and occasional demand for their own, in return, could not but expose them to a state of impoverishment, compared with the opulence to which their political and natural advantages authorise them to aspire.

Source: The Tragedy of Great Power Politics (2001), Chapter 10, Great Power Politics in the Twenty First Century, p. 398

Report on Manufactures (1791)

Attributed to Washington in "Farewell to the United States of Europe: long live the EU!" by André Fontaine at Open Democracy (29 November 2001) http://www.opendemocracy.net/democracy-europefuture/article_344.jsp. It appears to have originally circulated in French:
:: Je suis citoyen de la Grande République de l'Humanité. Je vois le genre humain uni comme une grande famille par des liens fraternels. Nous avons jeté une semence de liberté et d'union qui germera peu à peu dans toute la Terre. Un jour, sur le modèle des Etats-Unis d'Amérique, se constitueront les États-Unis d'Europe. Les États-Unis seront le législateur de toutes les nationalités.
: An anonymous blogger in "Did George Washington predict a "United States of Europe"? (30 January 2010) http://racehist.blogspot.com/2010/01/did-george-washington-predict-united.html showed that it derived from Gustave Rodrigues, Le peuple de l'action: essai sur l'idéalisme américain (A. Colin, 1917), p. 207:
:: Washington écrivait à La Fayette qu'il se condérait comme « citoyen de la grande république de l'humanité » et ajoutait : « Je vois le genre humain uni comme une grande famille par des liens fraternels ». Ailleurs il écrivait, prophétiquement: « Nous avons jeté une semence de liberté et d'union qui germera peu à peu dans toute la terre. Un jour, sur le modèle des Etats-Unis d'Amérique, se constitueront les États-Unis d'Europe. »
: A translation by Louise Seymour Houghton ( The People of Action: An Essay on American Idealism (1918) http://books.google.com/books?id=b8Y9AAAAYAAJ) reads:
:: Washington wrote to Lafayette that he considered himself a "citizen of the great republic of humanity," adding: "I see the human race a great family, united by fraternal bonds." Elsewhere he wrote prophetically: "We have sown a seed of liberty and union that will gradually germinate throughout the earth. Some day, on the model of the United States of America, will be constituted the United States of Europe." [pp. 209-210]
: The first two quotations come from a letter to the Marquis de Lafayette of 15 August 1786 (see above) as quoted in Joseph Fabre's Washington, libérateur de l'Amérique: suivi de Washington et la revolution Américaine (Ch. Delagrave, 1886), and the third is also found in that source where, although placed between quotation marks, it is clearly intended as the author's own comments on what "Washington and his friends" were saying to the world by establishing the American Constitution. Gustave Rodrigues mistakenly printed Fabre's words as Washington's alongside some actual observations of his from a letter to Lafayette, and so created the misquotation.
Misattributed

Source: The Tragedy of Great Power Politics (2001), Chapter 2, Anarchy and the Struggle for Power, p. 43

Source: The Political Economy of International Relations (1987), Chapter Eight, International Finance, p. 308

Alors, il est vrai que la Patrie est un élément humain, sentimental et que c’est sur des éléments d’action, d’autorité, de responsabilité qu’on peut construire l’Europe. Quels éléments? Eh bien, les États, car il n’y a que les États qui, à cet égard, soient valables, soient légitimes et en outre soient capables de réaliser… J’ai déjà dit et je répète, qu’à l’heure qu’il est, il ne peut pas y avoir d’autre Europe possible que celle des États, en dehors naturellement des mythes, des fictions, des parades. De cette solidarité dépend tout espoir d’unir l’Europe dans le domaine politique et dans le domaine de la défense, comme dans le domaine économique. De cette solidarité dépend, par conséquent, le destin de l’Europe tout entière, depuis l’Atlantique jusqu’à l’Oural.
Press conference, Elysée Palace, Paris, 15 May 1962
Fifth Republic and other post-WW2

Source: Kritik der zynischen Vernunft [Critique of Cynical Reason] (1983), p. 77

17 U.S. (4 Wheaton) 316, 406-407
McCulloch v. Maryland (1819)
Context: [T]he Government of the Union, though limited in its powers, is supreme within its sphere of action. This would seem to result necessarily from its nature. It is the Government of all; its powers are delegated by all; it represents all, and acts for all. Though any one State may be willing to control its operations, no State is willing to allow others to control them. The nation, on those subjects on which it can act, must necessarily bind its component parts. But this question is not left to mere reason; the people have, in express terms, decided it by saying, [p406] "this Constitution, and the laws of the United States, which shall be made in pursuance thereof," "shall be the supreme law of the land," and by requiring that the members of the State legislatures and the officers of the executive and judicial departments of the States shall take the oath of fidelity to it. The Government of the United States, then, though limited in its powers, is supreme, and its laws, when made in pursuance of the Constitution, form the supreme law of the land, "anything in the Constitution or laws of any State to the contrary notwithstanding."