Borger: Dems mistake on Benghazi

• Gloria Borger: Republicans in Congress name a committee to investigate Benghazi


• She says Democrats would make a mistake if they go through with boycott of panel


• Political subtext of Benghazi probe is GOP effort to get voters to turn out in November, she says


• Borger: If Democrats skip the hearings, they lose their influence, access to evidence

(CNN) -- No doubt about it, Republicans have latched on to a red hot potato when it comes to the controversy of who-did-what-when in Benghazi.

The awful story of a terrible embassy attack, a botched aftermath and finger-pointing about what more could have been done has already been the subject of an exhaustive internal State Department investigation and congressional hearings.

And the truth is that mistakes were made, everyone is somehow to blame and four people are dead who should not have died. It's a terrible mess.

It seemed to be settling down a bit until last week. That's when the State Department -- after a request made under the Freedom of Information Act -- released a memo by a senior White House adviser that tried to "underscore that these protests are rooted in an Internet video, and not a broader policy failure."

Republicans cried foul, especially when the White House offered the weak explanation that the e-mail was not specifically about Benghazi but rather about the "general dynamic" of the Muslim world at the time. Never mind that it was written as then-U.N. Ambassador Susan Rice was about to go on Sunday shows to discuss the event.

So now comes a congressional inquiry -- a new panel with 7 GOPers and 5 Democrats. This time, it's the Democrats who are crying foul, and they're threatening to boycott the committee. I get it: They believe it's a witch hunt, and they don't want to participate. Why legitimize it? Why give it more credence? Why play into GOP hands?

Here's why: If you don't participate, you can't defend. And if you can't defend -- or explain -- you lose. It's as simple as that.

New Benghazi committee pursuing Clinton

Smoking gun or partisan nonsense?

This is what's truly going on. This is a short-term political play by Republicans that, they hope, could also have some long-term implications for Hillary Clinton as a presidential candidate in 2016. After all, this happened on her watch as secretary of state. That job is one of the major line items on her resume. If the public's assessment of that tenure is called into question, then the value of that job experience is diminished.

But there's a more immediate political play here. Midterm elections are occasions for partisan mobilization, plain and simple. In presidential years, the candidates are about the business of persuading independent voters to give them a shot.

In midterm elections, it's about the partisans. Of the 40% of the electorate that generally shows up, almost no one is up for grabs. Candidates just need to get their party's loyalists to turn out.

For Republicans, Motivator No. 1: Obamacare (or Obama). Motivator No. 2: Benghazi (or Hillary). So long as the economy keeps chugging along nicely, these issues become even more paramount.

Sure, there's a danger of overreach. There always is. (See: Bill Clinton and impeachment.) But Republicans aren't worried about that now, because their partisans are, well, partisan. This is a play for November.

In presidential elections, there's often a huge public appetite for a more forward-looking and affirmative candidate with a plan and a positive message and vision. But midterms are different. They're about partisan bloodletting.

So if the Democrats decide to boycott the committee, it's at their own risk. They will lose out on the conversation, no matter how silly they think it is. They will be uninformed about witnesses, strategies, subpoenas.

As Democrats learned during their participation in the "Fast and Furious" investigation, access to documents is a plus. You can play the game the way you want, leak what you want, tell your own narrative with the facts as you see them. No storyline left behind.

If the Democrats boycott, they may see themselves taking the high road. Trouble is, it could lead them nowhere.

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