As a matter of phrase that might technically be right. But where the idea of 'American Exceptionalism' really comes from, where its roots in American political discourse originate is from a trio of American political scientists and historians working in the aftermath of World War II and trying to explain America's under-explained success. The big three, I would say, were Louis Hartz, Daniel Boorstin and perhaps Richard Hofstadter.
The basic question these guys were trying to answer was why did American turn out, from one perspective, so well? How and why was it able to avoid all the bloodletting and conflict which beset Europe (obviously this was a particularly glaring contrast in the late 40s and early 50s.) The key seemed to come down to the absence, or relative absence, of class conflict. Some were ambivalent about it. Remember, Toqueville - the progenitor of a lot of this thinking - thought America's distinctiveness bred a cultural mediocrity. Others like Boorstin thought it was unambiguously a great thing.
Obviously, the lack of class conflict in American history is a questionable proposition in itself about which many millions of things could be said. A deeper problem was the idea that if the recent history of the United States was significantly different from that of Britain, France and Germany that the normal laws of human historical development didn't apply to America.
The key point though was that there were key laws of history that didn't apply to America. That had allowed the US to arrive at a deep-rooted level of political consensus, enjoy general prosperity and lack class conflict as a basic driver of our history. In this sense, these 1950s academic intellectuals agreed with those Communists having their obscure discussion in the 1920s. They just saw as a good thing what the Communists saw as a bad thing. They agreed on seeing Western Europe as the baseline of how human societies evolve, a rather dubious assumption.) That's what 'exceptionalism' meant - that the US got a pass on certainly laws of history that applied to the rest of the world - as though a particular person got a pass on insecurity and sadness.
And yet in the post-2009 Palin era - and seemingly everywhere now, no longer just Palin - the whole concept got a rebirth with a not very subtly different meaning of the word. 'Exceptionalism' got its 'ism' like off and became 'exceptional' as in, awesome. Like we are exceptional, booyah!
I don't want to pretend that 'exceptionalism' was ever sharply divided from a sense of American triumphalism or historical mission. It wasn't. But the current version of the debate is different and weird and seems to have gotten wrapped into Red America's package of cultural definition and insecurities.