It seems appropriate to sound a note of caution about the word "American," from
the point of view of the history of the language.  To assume that the usage of
the word in the 17th and 18th centuries (prior to the Revolutionary and Federal
period) is the same as it is today may be misleading.  Denotations of words
change over time.  While in some cases the word "American" may have denoted a
growing sense of cultural identity, it also indicated--perhaps more
often--simple geographical (continental) location.

For a thorough account of the usage, here's the OED:

  A. adj.

    1. a. Belonging to the continent of America. Also, of or pertaining to its
inhabitants.
1598 SYLVESTER Du Bartas I. iii. (1641) 25/1 Under the Empire of the Ocean,
Atlantike, Indian, and American. 1633 HERBERT Temple, Ch. Mil. 235 Religion
stands on tip~toe in our land, Readie to pass to the American strand. 1773
BARRINGTON in Phil. Trans. LXIII. 285, I have happened..to hear the American
mocking-bird. 1885 Century Mag. Apr. 953/2 To use an expression made popular,
we believe, by General Hawley some years ago.., dynamiting is ‘not the
American way’! 1937 HEMINGWAY To Have & Have Not III. xvi. 232 The Colt or
Smith and Wesson..so well designed to end the American dream when it becomes a
nightmare. 1960 Observer 17 Jan. 20/6 The spread of personal prosperity in
America has led away from, rather than towards, the American Dream. Ibid. 20/7
The American Dream, the reasonable expectations of Americans, are by tradition
that all men shall be equal. 1961 M. MCCARTHY On the Contrary (1962) I. 40
Apologists for the American Way of Life find themselves condoning injustices.

    b. American language (usu. with the),    (i) a language of American Indians;
   (ii) American English (see sense 3). Also American tongue.
1643 J. LANGLEY in R. Williams' Key into Lang. of Amer. 200, I have read over
these thirty Chapters of the American Language, to me wholly unknowne. 1689 I.
MATHER Brief Relation of State of New Engl. 16 In an Indian Town..was an
Englishman, who being skilful in the American Language, Preached the Gospel to
them in their own Tongue. 1789 WEBSTER Dissertations Eng. Lang. i. 22 Numerous
local causes..will introduce new words into the American tongue. 1800 in
Mencken Amer. Lang. (1936) I. i. 11 (title) On the Scheme of an American
Language. Ibid., Grammars and dictionaries should be compiled by natives of the
country, not of the British or English, but of the American tongue. 1839 Penny
Cycl. XIII. 320 The singular congruity in structure between all the American
languages, from the northern to the southern extremity of the continent. 1936
MENCKEN Amer. Lang. (ed. 4) I. iii. 23 This occasional tolerance for things
American was never extended to the American language.

    2. a. Belonging to the British colonies in North America (obs.).    b.
Belonging to the United States.
1647 WARD Simple Cob. 24 Divers make it an Article of our American Creed. 1775
JOHNSON (title) Taxation no Tyranny, an Answer to the Resolutions and Address
of the American Congress. 1883 Daily News 14 May 5/8 The plain evening dress
which bespeaks the American Minister everywhere.

    c. U.S. spec. (See quot. a1861.)
1837 Diplom. Corr. Texas (1908) I. 187 A large number of fine American
horses..which there is no doubt had been stolen from citizens of Texas. 1846 E.
BRYANT What I saw in Calif. (1849) iv. 37 Such [Indians] as rode ponies were
desirous of swapping them for the American horses of the emigrants. a1861
WINTHROP John Brent (1862) ii. 14 He was an American horse,{em}so they
distinguish in California one brought from the old States. 1878 J. H. BEADLE
Western Wilds, xvi. 253, I rode a good-sized American horse.


 B. n.

    1. An American Indian.
1578 G. BEST Frobisher's Voy. (1867) 284 The Americans..which dwell under the
equinoctiall line. 1632 MASSINGER City Madam III. iii, Worse Than ignorant
Americans. 1711 ADDISON Spect. No. 56 {page}1 The Americans believe that all
creatures have souls. 1777 ROBERTSON Amer. II. 417 Amazing accounts are given
of the persevering speed of the Americans.

    2. A native of America of European descent; esp. a citizen of the United
States. Now simply, a native or inhabitant of North or South America (often
with qualifying word, as Latin American, North American); a citizen of the
United States.
1765 GALE in Phil. Trans. LV. 198 Paying quit-rents to monopolizers of large
tracts of land, is not well relished by Americans. 1775 JOHNSON Tax. no Tyr. 13
That the Americans are able to bear taxation is indubitable. 1809 KENDALL Trav.
II. lviii. 286 The Americans, that is the subjects of the United States. 1882
HOWELLS in Cent. Mag. Nov. 26 We Americans are terribly in earnest about making
ourselves.

    3. A ship belonging to America.
1817 SOUTHEY in Q. Rev. XVII. 2 He had sailed in an American to Manilla.

    4. pl. Short for American stocks or shares.
1886 Times Reg. Events in 1885, p. cliii, People..who..had come to believe that
‘Americans’ would never advance any more. 1897 Daily News 7 Sept. 7/1 A
further rise in Americans. 1905 Daily Report 22 Mar. 1/2 Yankees. As predicted
yesterday, Americans have quickly recovered their reaction.

    5. American English; the form of English spoken in the United States.
[1782 CHASTELLUX Voyages dans l'Amérique (1786) II. 202 Vous parlez bien
américain.] 1802 Port Folio 28 Aug. 266/2 [A Latin verse] which my
schoolmaster has translated into American. 1803 J. DAVIS Trav. U.S. 139 What do
you think of the style of Johnson, the Reviewer? It is not English that he
writes, Sir; it is American. 1869 GILLMORE Accessible Field Sports 19 But it
was evident I was not boss. [Note] American for ‘master’. 1889 KIPLING From
Sea to Sea (1899) xvii. 368 The American I have heard up to the present, is a
tongue as distinct from English as Patagonian. 1908 Daily Chron. 10 June 6/7
English spoken; American understood. 1919 MENCKEN Amer. Lang. 26 American thus
shows its character in a constant experimentation,..a steady reaching out for
new and vivid forms. 1966 Listener 2 June 810/3 We have tried..to translate
from French into American and vice versa.


So... to assume the word "American" indicates a proleptic sense of national or
cultural identity may be anachronistic.


Cheers -- Kevin