Some people notice this, and some don't: the most important Tea Party groups in America generally hate each other.

It's a facet of a disjointed movement that has strived, from its outset, to remain "grassroots" and leaderless, and which is hypersensitive to any attempts at outside control. Mark Meckler, a national co-coordinator of Tea Party Patriots, the nation's largest Tea Party membership group, is fond of saying that everyone in the movement is a leader.

But as the movement has gained traction since early 2009, an infrastructure of large, significant national groups has arisen both as an outgrowth and a support mechanism, and they are playing a larger role in U.S. politics every week.

So, with that in mind, here's a guide to which ones don't like each other, and why:

Tea Party Patriots is the most notorious hater of Tea Party groups that aren't "grassroots" enough. The group is a national membership organization that at one point estimated 15 million members (though the number is probably impossible to count). They pride themselves on not having a "leader," per se, and on simply helping local activists across the country communicate and learn from each other, via a social networking site and regular conference calls.

Most notably, TPP's Meckler has questioned the grassroots credibility of Tea Party Express, the group run by GOP consultant Sal Russo that has raised and spent campaign money to deliver victories in Nevada, Alaska, and Delaware. "They are the classic top-down organization run by G.O.P. consultants, and it is the antithesis of what the Tea Party movement is about," Meckler told the New York Times recently. TPP organizers have also called Tea Party Express "racist," due to the anti-Muslim rantings of its former front man, Mark Williams, who stepped aside earlier this year.

The feeling is mutual: Russo told me recently that Meckler is an "idiot." (More on this in a forthcoming interview to be published in National Journal.)

Adding to this TPP/TPE intrigue: TPE's current chairman, Amy Kremer, is a former member of TPP who was essentially expelled from the group for associating with TPE.

TPP also has problems with Tea Party Nation, which hosted the first-ever Tea Party convention in Nashville last winter. High ticket prices, a rumored/reported $100k speaking fee to Sarah Palin, and TPN's for-profit status led Tea Party Patriots to abstain from participation, encourage other people not to participate, and criticize the whole thing.

TPP also decided not to join the National Tea Party Federation, a loose collection of national and local Tea Party groups that coordinates responses to attacks on the movement, suspecting a top-down power-grab.

The National Tea Party Federation, meanwhile, doesn't get along with Tea Party Express. A founding member of the coalition, Tea Party Express was booted from it in July when chairman Mark Williams penned a controversial blog post that compared the NAACP to slave traders. NTPF issued an ultimatum that TPE must disassociate from Williams and announce his departure publicly. (Williams had said some controversial things before and had said he planned to step aside, but he had remained listed as "chairman" on the TPE website.)

Standing on the sidelines of all this is FreedomWorks, the Dick-Armey-led group that works with and trains local Tea Party activists. They've tried to remain neutral as controversies have arisen. President and CEO Matt Kibbe has said more than once that FreedomWorks prefers to "let a thousand flowers bloom." The strongest criticism he offered publicly of the first Tea Party convention was to the effect of, "That's maybe not the way we would do things." FreedomWorks retains an "affiliated relationship" with the National Tea Party Federation. It has hosted TPP's Meckler and fellow co-coordinator Jenny Beth Martin during an activist training event at its headquarters in DC.

There remain feelings of bitterness toward some of these groups from individual activists, as well. One incensed former Tea Party Patriots member, for instance, complained to me that TPP doesn't disclose its finances and insinuated the group is corrupt. He also complained that TPE exists for the sole purpose of enriching Russo (Russo, for his part, insists he hasn't made a dime off the movement).

All of this presents a daunting landscape of bitter recriminations and political booby traps for any politician seeking to approach the Tea Party.

When Sarah Palin chose to make her Tea Party debut by speaking at the Tea Party Nation convention in Nashville in February, some activists grumbled that she was making a mistake. As criticism of the convention grew louder, Reps. Michele Bachmann and Marsha Blackburn withdrew from the event in the weeks leading up to it. Palin was also criticized by TPE's critics for her decision to speak at a TPE event in Searchlight, Nevada and ride on the group's tour bus.

People like to talk about the Tea Party movement as if it's one thing, but this couldn't be further from the truth. Interestingly enough, no one in particular is struggling to become the movement's leader, or even its most influential voice. The combatants in this infighting, by and large, recognize that the movement is something that exists outside of them, that it's a force they can harness or foster but never really control.

Which makes the infighting all the more chaotic.

We want to hear what you think about this article. Submit a letter to the editor or write to