It's telling that the question is only asked in the wake of a sex scandal -- and not to verify the honesty of broader claims

During Herman Cain's press conference on sexual harassment allegations, Steve Futterman of CBS News asked, "You are basically now in a he-said, she-said situation. She's saying something, you're saying something, they're both diametrically opposed to each other. As distasteful as it might be, would you be willing to do a lie detector test to prove your honesty in something like this?"

"Yes!" Herman Cain replied. "But I'm not going to do that unless I have a good reason." It's a fascinating exchange. The question is dramatic; the answer unhesitating, yet slyly hedged. And what sort of reason, beyond four women making accusations of misconduct, would do the trick?

That's what I thought as I watched the press conference.

As I reflect on it, however, I have a darker reaction. The more I think about the exchange, the more it seems to me a damning commentary on the absurd prominence sex scandals have in our politics. That isn't to minimize the seriousness of superiors sexually harassing their subordinates, or to indict Futterman, the CBS newsman, for asking a perfectly defensible question.

But ponder this.

Every four years, we elect a man or woman who'll control the nuclear arsenal of the United States, act as commander in chief of the military, hold sway over the CIA, FBI, and DEA, among other parts of the bureaucracy, and who is effectively able to start a war with any country on the planet without so much as consulting or even notifying Congress or the American people. He or she is arguably the most powerful person on the planet, and certainly in the U.S.

When does it occur to us to request that a candidate for that job submit to a truth-gauging device so that we can accurately gauge his or her honesty? Only when there is a charge of sexual misconduct! It would be unthinkable for a reporter to ask, "Would you submit to a lie detector test, Mr. Romney, so that we can settle once and for all whether you think the individual mandate is a good idea?" A member of the press wouldn't dare to ask, "Before you tell me whether you're inclined to pull troops out of Afghanistan, Gov. Perry, would you strap on this monitor?"

But the lie detector question didn't seem surprising or out of place in the press conference. It seemed totally normal to most everyone watching to invoke the technology when the subject was sexual harassment.

Isn't that telling?

It neatly reveals the subjects we're subconsciously inclined to delve into most aggressively. Odds are high that Cain will never in fact take a like detector test. But just as a hypothetical, say a week from now he is still the frontrunner for the GOP nomination, he sits down in a chair hooked up to a lie detector machine, and offers to answer one question on any subject, but just one.

Should the chosen reporter resolve the he-said she-said?

Or would that be squandering the question?