"Restoring American Exceptionalism" has recently become an important Republican slogan. It's a featured theme for Newt Gingrich, Rick Santorum, and Glenn Beck. Mitt Romney and Ron Paul at least bow in its direction, as do Rick Perry and Sarah Palin. Last month, there were hundreds of "Restoring American Exceptionalism" events during National School Choice Week (Jan. 22-28, 2012), under the leadership of the Americans for Prosperity Foundation, founded by David H. Koch.
The odd thing about this is that "American Exceptionalism" was originally a Communist doctrine motivating a moderate and reformist approach to revolutionary organizing, developed and fiercely argued in the 1920s and 1930s; and the term was revived, with a similar meaning but a different motivation and emphasis, by liberal political scientists and historians in the 1950s.
The OED's gloss for the entry exceptionalism jumps on this leftist history without even needing the modifier American:
The theory that the peaceful capitalism of the United States constitutes an exception to the general economic laws governing national historical development, and esp. to the Marxist law of the inevitability of violent class warfare; more generally, the belief that something is exceptional in relation to others of the same kind; loosely, exceptional quality or character.
Until the 1970s, all the OED's citations are from communist or at least Marxist sources:
[1928 J. Lovestone in Communist Nov. 660 We are now in the period of decisive clashes between socialist reformism and communism for the leadership of the majority of the working class. This is in all countries of high capitalist development with the exception of the United States where we have specific conditions.]
1929 Brouder & Zack in Daily Worker (N.Y.) 29 Jan. 3/2 This American ‘exceptionalism’ applies to the whole tactical line of the C.I. as applied to America. (This theory pervades all the writings and speeches of the Lovestone–Pepper group up until the present.)
1945 Political Affairs July 603/2 When we argued against Jay Lovestone, who was expelled from our ranks years ago, we pointed out that Lovestone‥put forth his theories of exceptionalism because he was influenced by the exaggerated strength of American imperialism.
1957 E. R. Browder Karl Marx & Amer. iii. 29 The exceptionalism of America is one of concrete historical conditions, but not of laws and principles of economic development.
However, liberal historians recycled the phrase during the 1950s, as Michael Rogin explains in this passage from Ronald Reagan, the Movie, and other episodes in political demonology, 1988:
The doctrine of American exceptionalism developed within a wing of American Communism in the 1930s to explain the failure of Marxian socialism to take root in the United State. American exceptionalists contrasted the limited and superficial conflicts in America to the more tenacious social and political divisions that had generated revolution and dictatorship. American exceptionalism thus underlay the consensus interpretation of American politics offered by such writers as Richard Hofstadter and Louis Hartz, interpretations that dominated the 1950s. The United States, these scholars claimed, lacked the class loyalties, the fixed and deeply rooted statuses, and the powerful state structures of societies with feudal and absolutist pasts. Consensus historians attributed American distinctiveness to such factors as material abundance, the pervasiveness of liberal individualism, social and geographic mobility, ethnic conflict, and a pluralist political tradition. They argued that this combination of factors created political fragmentation within America instead of one or two large and explosive divisions.
Countersubversives, in this view, failed to grasp the fundamental harmony of American political life. Importing Europen fears into America, they imagined enemies that did not exist. They transformed American pluralist realities into an imaginary, two-sided struggle between the forces of good and an empire of evil. [...]
Men like Hofstadter, Seymour Martin Lipset, and Daniel Bell, who pioneered the symbolist approach, came from an immigrant, urban milieu and had been socialists in their youth. They turned away from Marxist categories in part by invoking the distinctive features of American life that had discouraged a class-based, ideological socialism and encouraged irrational, status-based movements instead. American history, as they saw it in the 1950s, was characterized not by the presence of revolutionary subversives but by (in McCarthyism) the irrational obsession with them. Deriving the paranoid style from ethnic and status-based conflicts in nontraditional, mobile, affluent society, Hofstadter and his colleagues were shifting from a doomed search for what the United States shared with Europe to a discovery of what was distinctively American. Diversity made a cosmopolitan liberalism dominant in American life, they believed, particularly once the New Deal admitted the immigrant working class to a share of political and economic power. But the paranoid style was the price America paid on its margins for the complexity, tolerance, and interest-orientation at its center. [...]
In classic American fashion, however, these historian children of immigrants were turning their own autobiographies into American history. They were elevating the conflicts between immigrants and natives, the upwardly mobile and the downwardly mobile, into the central principle of non-interest-based American historical conflict. Protestants from the American hinterland — nativists, abolitionists, Populists, and Klansman — were the alleged sources of the paranoid style. It was as if the children of immigrants were saying to their old-family targets, "You had the fantasy that our parents were dangerous to you; that fantasy made you dangerous to them. When America belonged to you, you tried to exclude us. Now with the New Deal, it belongs to us as well. But whereas you had only superstition and religion to delegitimize us, we can use modern, scientific methods to discredit you."
Given this, it's ironic that Fred Koch, founder of Koch Industries, was one of the founders of the John Birch Society, a key analytic target of Hofstadter's essay on "The Paranoid Style in American Politics".
The Wikipedia article on American exceptionalism offers a rather more pastel picture, citing a 2011 Gordon Wood quote about "our idea that we Americans are a special people with a special destiny to lead the world toward liberty and democracy", and asserting that "This observation can be traced to Alexis de Tocqueville, the first writer to describe the United States as "exceptional" in 1831 and 1840". Seymour Martin Lipset and Gary Marks also make the connection to de Tocqueville in It Didn't Happen Here: Why Socialism Failed in the United States, 2000:
The United States, as noted by Alexis de Tocqueville and Friedrich Engels, among many visitors to America, is an "exceptional" country, one uniquely different from the more traditional societies and status-bound nations of the Old World. The term "American exceptionalism," first formulated by Tocqueville in the 1830s, and since used in general comparative societal analyses, became widely applied after World War I in efforts to account for the weakness of working-class radicalism in the United States.
As far as I can tell, this history is inaccurate. Tocqueville did not use the (French equivalent of) the term "American exceptionalism", but rather wrote that "La situation des Américains est … exceptionnelle", and made this observation in a completely different context, arguing that "l'exemple des américains ne prouve point qu'un peuple démocratique ne saurait avoir de l'aptitude et du goût pour les sciences, la littérature et les arts" ("the example of the Americans does not prove that a democratic people can have no aptitude or taste for science, literature, and art"):
Je ne puis consentir à séparer l'Amérique de l'Europe, malgré l'Océan qui les divise. Je considère le peuple des États-Unis comme la portion du peuple anglais chargée d'exploiter les forêts du Nouveau Monde, tandis que le reste de la nation, pourvu de plus de loisirs et moins préoccupé des soins matériels de la vie, peut se livrer à la pensée et développer en tous sens l'esprit humain.
In spite of the ocean that intervenes, I cannot consent to separate America from Europe. I consider the people of the United States as that portion of the English people who are commissioned to explore the forests of the New World, while the rest of the nation, enjoying more leisure and less harassed by the drudgery of life, may devote their energies to thought and enlarge in all directions the empire of mind.
And in fact, I haven't been able to find any uses of the term "American exceptionalism" earlier than the OED's 1929 Daily Worker citation, which is a dozen years past the end of WW I.
Its recent revival may involve a tinge of "those Europeans are socialists but we're not", but the third-generation term "American exceptionalism" seems in most cases simply to be an alternative term for American patriotism: "American exceptionalism" = "America is exceptionally great". Thus Glenn Beck:
This year, I as an individual and private citizen stand at those crossroads and boldly declare my choice. I will not accept that America’s best days are behind Her, that there is no such thing as American exceptionalism.
Campaign materials from Newt Gingrich:
The video features Callista Gingrich addressing “American exceptionalism,” …
“Growing up in Whitehall, Wis., an all-American Midwestern town, it was impossible not to be instilled with a sense of patriotism,” she said. “As a young person, I was surrounded by people who believed in the greatness of America and were unapologetic about those beliefs.”
Rick Parent said: "I am proud to endorse Rick Santorum for President. There is no candidate in the field who shares more of my strong faith in family and American exceptionalism than Rick Santorum. Rick Santorum has stood tall for Life, for the traditional family, and for the defense of our nation. His core values are what I consider key to what is needed in our nation's leadership moving forward in the great American Reformation."
From Mitt Romney's:
“President Obama’s economic policies have failed the citizens of Nevada. Nevadans cannot afford four more years of these policies, which have resulted in high unemployment and foreclosure rates,” said State Senator Michael Roberson. “Mitt Romney has the private sector background, along with his experience as Governor of Massachusetts, to balance the budget, create jobs, and provide the stability in Washington that will guarantee American exceptionalism.”
I don't know exactly when this third-generation usage began, or what forces drove its spread; but it seems to have started within the past decade.
And to forestall mistaken criticism, I should note that I personally endorse all three meanings of this phrase.