So who are the four geniuses who got arrested by the FBI yesterday for—apparently—trying to tap the phone of a sitting U.S. senator?

James O'Keefe, Robert Flanagan, Stan Dai, and Joseph Basel, were arrested by U.S. Marshals yesterday for "entering federal property under false pretenses for the purpose of committing a felony" after they allegedly dressed up as telephone repairmen and attempted to tamper with the phones of Sen. Mary Landrieu's New Orleans office. O'Keefe is 25 years old, the rest are all 24.Here's what we know about them:

James O'Keefe
O'Keefe came to fame last summer when he and his colleague Hannah Giles dressed up for Halloween early and walked into ACORN offices nationwide pretending to be a hooker and a pimp seeking tax advice, thereby blowing the lid off the sordid scandal that was ACORN's free tax advice to people pretending to be hookers and pimps. The sting was tightly coordinated with the launch of Andrew Breitbart's and promoted beyond saturation by Fox News, which heralded the pair as the conservative answer to 60 Minutes. We've asked Breitbart whether O'Keefe and his pals were on assignment for Big Government when they were arrested, but haven't heard back. The Washington Independent's David Weigel says his sources are saying they weren't.

And, of course, Fox News, which was one of the outlets that pushed hardest to turn O'Keefe into a folk hero, is taking the position that this Landrieu office incident is a story "that probably needs a lot of context and a lot of looking into" before anyone jumps to conclusions. Unlike, say, videos of a white boy in garish pimp clothes which are prima facie evidence of ... something.

Robert Flanagan
Flanagan is the son of William Flanagan, the acting U.S. Attorney for the western district of Louisiana. Which makes it rather awkward that he was arrested in, and is being prosecuted by the U.S. Attorney for, the eastern district of Louisiana. The elder Flanagan ascended to the gig just one week ago after his Bush-appointed boss left office; none other than Sen. Mary Landrieu has submitted recommendations for his replacement to the White House. UPDATE: And Obama has nominated Landrieu's recommendation, Stephanie Finley. But Sen. David Vitter has placed a hold on Finley's confirmation because he wants assurances from the White House that Jim Letten, the U.S. Attorney who will be overseeing Flanagan's prosecution, won't be replaced. In other words, Flanagan's dad only has a job because the job of the guy who's prosecuting his son is in potential jeopardy. Vitter wants Obama to re-nominate Letten, a step that Landrieu says is redundant seeing as how he already has the job. Louisiana politics.

Stan Dai
Dai appears to be a long-time conservative rabblerouser: A Stan Dai was the head of George Washington University's Conservative Student Union, and a GWU student by the same name was quoted in 2004 in support of some pro-life student activists engaging in political theater at a John Kerry campaign event. And a then-17-year-old named Stan Dai in Naperville, Ill., told a USA Today reporter covering a student anti-war protest in 2003: "The people who organize the anti-war movement annoy me." This picture is from the Facebook page of a Stan Dai who attended GWU and is friends with Joseph Basel, one of the other plumbers busted yesterday. UPDATE: Lindsay Beyerstein finds two delightful datapoints about Dai: He was the recipient of a scholarship from the conservative Phillips Foundation, which also awards the Robert Novak Journalism Fellowship (he'd approve!), and he is an assistant director at Trinity Washington University's Intelligence Community Center of Academic Excellence, which trains people how to be spies.

SECOND UPDATE: Here's Dai discussing international terrorism and why emerging political leaders need to get "beyond the partisan" in a May 2008 interview conducted for the Junior Statesman Association, an organization that encourages high school students to get involved in politics.

Joseph Basel
A Joseph Basel is listed as one of 15 University of Minnesota-Morris College Republicans who attended Barack Obama's George W. Bush's second inauguration last year in 2005 with the help of Sen. Mark Dayton, and there's a Joseph Basel on Facebook who attends the University of Minnesota-Morris and is friends with Stan Dai and James O'Keefe.