David Letterman gave me one of my most cherished pop-culture memories: I was in the audience the night Sonny and Cher reunited on his "Late Show" stage in1987.      I wasn't a huge fan of the estranged couple, but I appreciated the poignancy of their joint appearance, punctuated by their "I've Got You Babe" duet.

       A former boss of mine at WKTI ended up being Letterman's supervisor at NBC, and it wasn't pretty.      Letterman derided him on the air, and was even more prickly when the cameras weren't on.       Dave seemed to have lost some of that meanness as the years went by, as he lost his shot at "The Tonight Show" to Jay Leno and moved his show to CBS.

       A bit of that meanness reappeared the other night, when he cracked off some jokes about Sarah Palin's daughter.      The one getting the most buzz is a line about the mother and daughter being at a Yankee game and Alex Rodriguez getting the girl pregnant.

       Not funny.

       The Palin camp is taking umbridge, especially since Letterman was referring to a 14 year old girl (who actually went to the stadium).      Letterman maintains he was talking about 18 year old Bristol who had a child by her high school boyfriend.

       I don't know many rules of comedy, but decency dictates that kids aren't in play, regardless of the age.     Most candidates respect that when on the stump, and even the voracious White House press corps abides by the invisible fence that envelopes the family quarters.    NBC tried to get to the Obama girls during their just-completed "Inside The White House" series, but the First Couple said "no".

        The Bristol Palin story got a lot of buzz last summer when news of her pregnancy got ferreted out.     Some found that fact alone distasteful, but I don't know how it could be ignored.     The Palins didn't hide her, and she has since gone on to become a spokesperson for abstinance.       She certainly didn't want to be in the public eye, but by choice has chosen to stay there.

       That still doesn't make what Letterman did right.      There's plenty of fertile comedic Palin ground to be plowed but that blade should never touch the kids.       Mom is the one in the political spotlight, which is also a bullseye.     Fire away.     Leave the kid alone.

        Don't ignore the timing of this--Letterman is getting plenty of pub at a time when his NBC counterpart, Conan O'Brien, is late night's new fair-haired boy.       Dave let the newly minted "Tonight" have his honeymoon, waiting a week or so before doing something off the charts.        Something tells me Letterman counted to five and then decided to let the world know that he still exists, even if he had to hit below the belt to do it.

       The Letterman/Palin dust-up is now a hot topic on cable news and talk radio.       The usual suspects are saying the usual things.     It has Dave in the news cycle, and it'll probably earn him a few extra viewers in the days ahead.     It's all part of the game.

       One that should leave it's hands off politician's children.