No surprise, as our own comments section split last week on the question of whether even reps as righteous as Mike Pence should be coopting the brand of a thoroughly grassroots, outside-the-Beltway movement. Here’s another question for you: What do the members of the caucus stand to gain in the long run from joining? People like Pence and Bachmann don’t need any labels to drum up support among rank-and-file righties; as for the rest, they’ll enjoy a little buzz headed into the midterms but long-term they’re going to be scrutinized by conservative activists even more closely than the average GOP member of the House is. If there’s already a “purity test” for congressional Republicans on most issues, why join a caucus where an even more exacting purity test will applied? Unless you’re a Pence or Bachmann and pretty much guaranteed to vote the conservative line on any issue, why box yourself in?

“If the tea party can stay in front of the caucus by vetting these members and monitoring their votes,” [Katrina Pierson] said, “it will be a good tool to hold these members accountable when liberal legislation is presented.”

Already, tea party activists have cried foul over one caucus member’s vote this month for the Democratic legislation overhauling financial regulations.

Pointing out that North Carolina Rep. Walter Jones was one of only three Republicans to support the bill, a writer on the influential Red State blog asserted “his membership on the Tea Party Caucus tells me they’ll take just about anybody. Kinda defeats the purpose, does it not?”

Bachmann has also come under tea party fire of late for her support of a pair of GOP congressional candidates opposed by tea partiers.

I assume that Paul Ryan, notwithstanding his attempt to deal with the entitlements crisis in a serious, systematic manner, would be drummed out of the caucus if he joined for having voted for TARP and the tax on the AIG bonuses. Am I wrong about that? Meanwhile, what happens on an issue like immigration reform or withdrawal from Afghanistan where there isn’t necessarily an orthodox “tea party position”? Will the caucus refuse to weigh in on those issues or will some sort of agreed-upon position be taken, even though it risks alienating some grassroots tea partiers? And what happens when, inevitably, some Tea Party Caucus member follows in Jones’s footsteps and votes for legislation that’s anathema to grassroots tea partiers? Is Bachmann prepared to actually kick people out of the caucus (and by what standard)? Or is everyone allowed to vote how they like, in which case there’s no purity test at all and the brand ends up standing for nothing?