There are derogatory terms flung around that have been part of the popular lexicon for as long as I can remember, but whose etymology is something I, at best, only make lazy assumptions about. One of those that has experienced a bit of a resurgence with the NATO bombing campaign in Libya is "isolationism". While the term could conceivably be as old as our republic, the US was pretty isolationist up through World War I. We were too busy making the Louisiana Purchase, taking Florida, bringing Texas aboard, taking the Southwest and the Northwest, and buying a firesale Alaska from Russia to, uh, pay attention to anything going on outside of our original 13 colonies.
So I turned to Google's handy Ngram viewer, which shows the incidence of selected words or phrases in published books over time, to trace the history of the term:
It looks like Pat Buchanan's unnecessary war spread the unnecessary phrase that, while having likely forever retreated from its WWII high, is still thrown around almost as loosely and carelessly as its other -ism cousins.