The problem with this argument is that many (if not most) political regimes adopt these elements at one point or another - I can certainly provide you with some first hand experienced examples from the other side of the Iron Curtain. Fascism, like mental disorder, is a continuum of human/political behavior, not a qualitatively different form of it. One of the most frequent mistakes of amateur psychologists is to grab a list of symptoms listed in the current version DSM and "diagnose" mental disorders by finding these symptoms in people they know or perhaps in themselves. The mistake of such a "diagnosis" is to concentrate on a selection of symptoms without considering their intensity, coexistence with other symptoms, or probabilistic matching overall behavioral patterns - which is what trained psychologists do.
The same can be said about "diagnosis" of fascism. The forms of political behavior found in decidedly fascist regimes can also be found in virtually any regime - the difference is that under fascist regime they are carried to an extreme. Therefore, to "diagnose" fascism it is not enough to identify the mere presence of a few elements of political behavior fund in fascist regimes but to identify broader clusters and intensity of such element that match those of known fascist regimes. Thus while it is no surprise to find fascist element in the US (as it is the case of any other country), those elements do not form clusters and intensity level of, say, Hitler's Germany or even Franco's Spain. Not even close.
Labeling US "fascist" is a demagogic hyperbole, which like any other form of demagoguery is designed to elicit emotional rather than rational responses - or to be more specific - to evoke those kinds of emotion that are instrumental in manipulating human behavior, chiefly fear and hatred. This is precisely why any rational person should refrain from demagoguery of any kind or political persuasion, be it left, right, or in-between.
Wojtek