By Yael T. Abouhalkah, Kansas City Star Editorial Page columnist

On Wednesday Barack Obama unleashed a new ad attacking Sarah Palin's qualifications for vice president. It's a cheap shot.

Obama was given a chance in a presidential debate in October with John McCain to state whether he thought Palin was qualified to be president of the United States.

Obama refused to answer the question, stating:

“That's going to be up to the American people. I think that obviously she's capable politician. She has, I think, excited the base in the Republican Party and I think it's very commendable, the work she's done on behalf of special needs.”

But in the new Obama ad, Obama takes direct aim at Palin.

The ad mocks McCain, pointing to his three-year-old quotation that "I know a lot less about economics than I do about military or foreign policy issues."

It continues with McCain's words that he may have to "rely on a vice president" to help with economic issues.

The ad says: "His choice?"

Then the ad wordlessly shows a smiling Palin at a speech, winking at the crowd.

I have no problem with Obama saying Palin was a horrible choice as a vice presidential candidate because she's unqualified to be president.

But Obama ducked the issue when given a chance to tell John McCain face-to-face that Palin was not qualified to be president.

Obama's last-minute attack ad was unfair.