The ironically hilarious part is that they believe they're fighting for freedom and against societies like the corrupt fundamentalism in Iran, yet if they have their way the US is going to look far more like a fundamentalist religious society than it has in its history.
Please describe the Tea Party plank that incorporates religious fundamentalism.
In contrast to your inaccurate knee-jerk categorization, the most salient Tea Party plank is the economy, and in particular, the national debt.
It's not a coincidence that the Tea Party movement is comprised entirely of purported conservatives, heavily backed by Fox News (Murdoch), and geographically situated in the most traditionally conservative and religiously-minded of the American States.
While their platform does not currently overtly discuss fundamentalist principles, we need only
look at the core values of their chosen candidates to see the correlation between the Tea Party movement and fundamentalist, often religiously-based, ideology. That's one example, but it's not an outlier. For an example of it in legislation, take a good hard look at some of the reasons that the recent health care changes were opposed in some circles: concerns over abortion, the definitive religious issue in public policy, ranked right at the top. As I recall, a handful of elected representatives received death threats as "babykillers" in the aftermath. Were the responsible individuals Tea Partiers? We don't know - but we do know that the Tea Party movement in general vehemently opposed the health care reforms and that religious concerns were incorporated into their reasoning, along with issues like the economy and expansion of federal authorities. This, I argue, will be the continuing trend - religious fundamentalism appended to conservative policymaking. The Tea Party movement is essentially taking the most authoritative, restrictive, and fundamentalist characteristics of libertarianism, conservatism, and religious morality and actively promoting that toxic mix in candidates under the guise of economic reform.
The economy is a focal point, but it essentially a red herring. Tea Party support isn't going to candidates that have the most sound understanding of economics - it's going to the candidate that can out-conservative their rivals, no matter how bat**** insane their platform.
So, I reiterate: if the Tea Party loons get their way, the cascade effect of the ideologies voted into office will conceivably reshape US policy to the most fundamentalist and religiously-based that it has been in its entire history. That's not hyperbole, it's the inevitable consequence of the continuing polarization occurring in American politics.