"...if they aren't even 'a party', then I find it even more ridiculous, that 'The Tea-Party' has held America ransom for two debt-ceilings already"
The function of a party is to collect the most important views for sizable portions of the voting populace. They have to be a kind of coalition for a representative type of government as opposed to direct democatic form of government.
And the reason becomes clearer if you look at what would happen without a party. Candidates would not have a central theme but rather just a mish mash of what is most important to them (to the degree they are ideological) or they spout adopted talking points they believe will induce the most votes (if they abandon principles of their own to become 100% poll responders). Both of those approaches by indiviual politicians, or the giant political stew of a full spectrum of mixtures of the two approaches, would create a field that could never evolve purposely towards or away from political ends. That would result in a large political engine that would fall prey to parasites, cronys, power grabbers, and corruption. (True, that's what we see today - but without parties it would happen faster and it would not offer a mechanism for correction.) A party is a lense through which voters can better focus their soviergnty.
It is the central theme that is defined by the logical or historical compatibiliity of the main principles from which a party is defined that generates a degree of life (from the base who are passionate about that theme). The GOP has a long history of mixing conservative principles, religious principles, and a "me-too" approach and that engenders far less excitement per capita. When the Democrats became progressives, they became better integrated around central themes that played well (granted, it's easier to do when you are willing to make dishonesty a key characteristic regarding theyour actual ends.)
The Tea Party has a much more tightly organized set of principles that speak to a large portion of the populace. AND it has no serpents head to cut off. That's important. This makes it a threat to both parties. That is part of the answer to why the GOP can't find a way to deal with it. To the Democrats, because is is a passionate set of principles that oppose progressive goals, they have no way to suck it in with identity politics, so they have to demonize it. Obama's administration has played almost every single issue, not to win on a position or to achieve a concrete goal, but to demonize any opposition, and THEN, when opposition is inadequate, do what they want. And the Tea Party is a threat to the GOP because it's passion and focus aim at power over the GOP from the grassroots - which is why the establishment tries to do end runs - like co-op the primary elections, and control campaign money. They need them as voters, they want their passion as a base in the general elections, but don't want to give them any power, and that puts the GOP in an ackward position. I can't imagine it lasting like this. Either the GOP moves to the right so that they become Tea Party in their establishment, or they go with the Democrats and demonize the Tea Party, which will result in the end of the GOP as an effective party. Either way, the progressives may have already sewed up the next few decades... maybe not, people can learn and they do have choices, and future events can change perspectives radically.
The Libertarian party doesn't really factor into this equation for two closely related reasons: 1) It is more of an ideological movement that is acting like a political party. This added function (being a party) to what would otherwise only be an intellectual movement gives educational advantages, media exposure, and more of a sense of realness - people can see that maybe some of these ideas could work in the real world. In this sense it is really more of an incubator and exposer of new political concepts then a functional political party (at this point in history). 2.) Because libertarians focus on idealistic end states, and while doing so, are not always focused on what can be achieved in a short time frame... i.e., because they ignore, on purpose, the time-requirements of the Overton window, they are self-marginalized to a degree in practical politics. I don't think this is bad, just the nature of politics. It is good that we have this experimental Libertarian party, to come up with ideas, to help shift the Overton window, and to grow till such a time that it simply replaces the GOP (which can't happen till the GOP is almost, but not quite libertarian on its own.)
The Tea Party is like common folks (i.e., not intellectuals or devotees of political science issues), who happen to be Overton window sensitive (by accident), and happen to be focused on taking the next step in the direction of libertarian goals, but they don't give a damn about the specific end states - not now. For now, they just want to move in the right direction on those things that make them Tea Party people (smaller government, less taxes, fewer regulations, balanced budget, and move towards living within the constitution.) That's very different from the libertarians who are arguing, for example, about the specific details of financing the ultimate minarchy. The Tea Party doesn't want to argue about the end states, or theoretical nuances, just about the direction and getting a good bite out of going that way.
The Tea Party movement is just one of the political forces that are opposing the otherwise unfettered march of progressives to completing their transformaton into socialism. The real opponent of socialism is Objectivism's strong ethical stand for individualism and the attendent Capitalistic system - which requires a constitutional government limited by explicit statements of individual rights that form the basis for all laws. I.e., minarchy.
The war won't be won by political forces that are battling. It has to be won at a cultural level where some critical mass is achieved of individuals intellectually aware of individual rights (of Objectivist views). That means generations of educational reform. So, the Tea Party - in tactical terms - are trying to hold some of the key bridges till the main forces arrive.
Marotta says, "...only Congress has the right to create money. That kind of traditionalist anti-capitalism is common across the right wing from organizations such as Spotlight, Birchers, and others who have a nationalist orientation." But there is nothing anti-capitalism about suggesting a move from a quasi-independent, but monopolistic agency printing money, to the more constitutional approach of having it in the hands of congress who, in theory and to a degree, are more in the hands of the voters. I like seeing a progression of steps from auditing the fed, leading to reducing the power of the fed, then getting to elimnating the fed, and to rules against fiat currency (gold standard?), and to legalizing private currencies, and finally to ending all government participation in money creation. And the steps are just to satisfy the psychological requirements of a kind of gradualism that is revealed in watching that Overton Window. If the media were supportive, and the events seemed to suggest it, then skipping a bunch of step would be great.