Poor Oprah (we should all be so poor). She found herself between a rock and a hard place on the question of whether to invite the newest, and probably the biggest, celebrity in the world on her show. To do Sarah or not to do Sarah? No good answer.

The ratings would be huge. And when someone in the entertainment business decides NOT to do something that would garner unbelievable ratings, that decision is always subject to scrutiny.

But Oprah’s decision to endorse Barack Obama for president last year has put her in an awkward place, straddling the roles of celebrity and politico, of entertainer and advocate, in a way that has probably done her far more harm than good, financially speaking. Endorsing Obama did not endear her to Hillary supporters who thought that if there were anyone in the world who should stand up for the first woman to mount a serious presidential campaign, it was Oprah. Was she putting race ahead of gender, racial solidarity ahead of ladies first?

Maybe. I didn’t agree with her preference, but I respected the courage and commitment it reflected. It did Obama a great deal of good, but it didn’t help Oprah any. The only reason to do it was principle.

Oprah has since tried to keep her personal politics separate from her show’s agenda. The minute I heard Sarah Palin wasn’t going to be invited, I checked, and indeed, it is absolutely true that since endorsing Obama, neither he nor his wife has appeared on her show.

So why should Palin? Because people are curious? Because she is, without question, the woman du jour? Because it would show Oprah’s “fairness”?

Or would it? If Oprah were to ask tough questions of Palin, ask her to defend her view that abortion should not be allowed even in cases of rape or incest, ask her about her support of “abstinence only” as the only form of sex education, ask her about her struggles to balance family and work, ask her the usual mix of personal and policy questions that she asks everybody else, she would almost certainly have everyone attacking her.

If it seemed like she was being tough on Palin, conservatives and their friends would say Oprah is beating up on her, Oprah is using her show for political purposes, Oprah is demeaning another woman to help her friend Barack. Precisely because she is Obama’s most famous supporter, even a completely straightforward interview would be dissected for moments of bias.

The truth is, only an interview consisting of one softball after another would avoid that charge of bias. But it would inflame Obama supporters who would then, with reason, accuse her of betraying her principles for her own sake, betraying her candidate and hurting the chances of the man she went out on a limb to support.

Heads: Sarah wins. Tails: Oprah loses. Not a winning sort of choice for America’s leading lady.

So Oprah did the only thing that seemed fair under the circumstances. She issued a statement saying Palin would be welcome, but after the election. It hasn’t stopped critics from piling on. But nothing would have. That’s what the space between a rock and a hard place looks like.