It's important to note, however, that in a 1990 article in the "Journal of World History", McNeill reflected that "The Rise of the West" must be viewed as "an expression of the imperial mood in the United States" and admitted that it could somewhat be seen as a "form of intellectual imperialism". Later, in a 1991 essay, McNeill emphasized that the unifying theme of his book was the importance of interrelation and cultural diffusion rather than a flat description of western history's effect on other civilizations.