You'll be forgiven for not knowing who Sidney Blumenthal is. If you don't, and you tuned in midway through Hillary Clinton's testimony before the House Select Committee on Benghazi, you might have concluded that Blumenthal is either a high-ranking al Qaeda leader, a Soviet spy, or some combination of Bernie Madoff and Ted Bundy. In any case, you might have concluded that he's a world-historical figure whose actions must be understood if America is to move forward into the future.

The ridiculously lengthy discussion about Blumenthal illustrates the problem Republicans have had with this entire investigation: They're stuck in their own bubble, unable to see what things might look like from outside it.

In case you don't know, Sid Blumenthal is a former journalist and longtime friend (and sometime employee) of the Clintons. For a variety of reasons, some more legitimate than others, Republicans regard him as a singularly sinister character. When it emerged that he had sent Hillary Clinton lots of emails about Libya (and other matters), they could barely contain their glee, going so far as to subpoena him to testify privately. He apparently failed to give them what they wanted, because up until now committee Chair Trey Gowdy has refused to release his testimony to the public. This is a replay of what happened in 1998 during the Monica Lewinsky scandal, when independent counsel Ken Starr forced Blumenthal to testify about what he knew in that case (if you want a lengthy explanation of Blumenthal and his relationship to the Clintons, go here).

The point is that, from within the Republican bubble, Blumenthal's connection to Benghazi, even if it consisted only of sending Hillary Clinton emails about Libya in general, proves that something fishy was going on. So naturally they'll waste an hour or two of her testimony talking about the fact that he sent her lots of emails, which proves that...he sent her lots of emails.

This is what happens when you start an investigation that you're sure will uncover evidence of nefarious goings-on. When you can't find any malfeasance, you convince yourself that even mundane things are nefarious, like the fact that Hillary Clinton has a friend you don't like.

Consider another topic of discussion at the hearing: the different stories that came out in the immediate aftermath of the attack explaining why the attack had occurred. The situation was chaotic, in large part because there were nearly simultaneous incidents at other American diplomatic outposts in the Middle East, growing out of protests of an anti-Muslim video that appeared online. At first, the administration said the Benghazi attack was like those in Cairo and Tunis, but it later became clear that it was more organized and planned (though the perpetrators may have opportunistically launched the attack precisely because so many protests were going on in so many places).

How should we understand the administration's changing explanation? Was it mere spin? A reflection of the information that was available? Or was it scandalous? Throughout, Republicans have treated the Obama administration's response as though it were not just scandalous, but possibly criminal. For instance, in May of last year, we learned of a memo that a White House communication official wrote at the time, encouraging staffers not to say Benghazi represented a failure of administration policy. In other words, a guy whose job it is to craft spin crafted some spin. But Republicans reacted as though they had caught Barack Obama personally killing those four Americans. "We now have the smoking gun," said Sen. Lindsey Graham. "It's the equivalent of what was discovered with the Nixon tapes," said Charles Krauthammer.

A similarly enlightening discussion was brought up in Clinton's hearing, with Republicans expressing such faux-outrage you'd think they were talking about one of the most diabolical propaganda campaigns in human history, and not a few comments that a few administration officials made to a few television shows. At another point in the hearing, a Republican congressman spent nearly 15 minutes aggressively interrogating Clinton over whether — brace yourself — her press secretary tried to make her look good to reporters. Only a truly diabolical figure could contemplate such a thing.

We're all tempted to assume the worst about our political opponents. They can't be just people we disagree with or even people whose values are different from ours. If we're partisan enough, we end up thinking that everything our opponents do is for the worst motives. Those people on the other side don't even make mistakes; when they screw up, it just shows how venomous their very hearts are. It's the political version of what psychologists call the "fundamental attribution error," in which we attribute our own actions to circumstance, but we attribute other people's actions to their inherent nature. If I cut you off in traffic, it's because I didn't realize you were in my blind spot; if you cut me off, it's because you're a jerk.

And if Americans died at Benghazi, well it just had to be an outgrowth of Hillary Clinton's infinite capacity for evil. She got emails from a guy we don't like? Proof of just how wicked the whole thing was! Somebody in the administration described the events in a way that turned out to be inaccurate? Yet more proof!

Many conservatives watching the hearing no doubt concluded that it reinforced everything they think about Clinton: that she's dishonest and untrustworthy, that she's surrounded by unsavory characters, and that she is utterly at fault for the deaths of those four Americans in Benghazi. They also probably thought the Republicans on the committee were heroic in their efforts to pin her down.

But it's hard to imagine lots of Americans who would agree, unless they are already committed Republicans. It wouldn't be the first time Republicans thought they were doing great, while the rest of America saw the situation a little differently.