Which reminds me: If you happen to be attracted to some of the broader ideas in an Ayn Rand book, you, my friend, are an extremist for life. If, on the other hand, your ideological education was provided by an all-star lineup of leftist thinkers, you're good. Certainly, no one is going to demand that you accept or repudiate the teachings of Frank Marshall Davis or Karl Marx in toto.
This is the world we're in. In Washington, extremists stand (somewhat) firm on the idea of preserving decade-long tax rates in a terrible economy, whereas reasonable presidents have no qualms heading toward a fiscal cliff, as long as they have a class-envy tax hike to campaign on (for what is, in the context of spending, a pittance).
As it turns out, radicals provide budgets that curb growth by a few percentage points over many years, whereas rational politicians don't even bother passing budgets.
Then again, Ryan the Unreasonable supported TARP, auto bailouts and Medicare expansions, so we can agree that radicalism does exist. It just depends, I suppose, on how you look at things.