Right up until Levi Johnston, Sarah Palin’s daughter Bristol’s ex-boyfriend, decided to pose underwear clad in Playgirl, he was a credible voice in the Alaskan wilderness about all things Palin. The Playgirl article, that will be the credibility-killing straw.

Wait. No it won’t.

Levi Johnson braying at the moon wearing nothing but boots and a polar bear pelt wouldn’t impair this young stud’s street cred with liberal media organizations. He’s trashing their favorite woman to hate, Sarah Palin. Alinsky’s Rule #2 and all that. One snarky wag called Johnston the “sanest member of the family.” Until he’s discarded as yesterday’s news, anyway.

It’s no surprise that Vanity Fair, the least fair of glossy liberal publications, would give a nice splashy spread to useful idiot Levi Johnston. He made revelations, man. The Truth is about to be revealed by a guy who named his kid for his favorite hockey equipment company.

Levi Johnston says far more about the sorry state of modern media than he says about the Palin family. Levi Johnston says more about the American Idol culture than he says about the Palin marriage. Levi Johnston reminds all of us why many feel shame at weddings and family reunions. There’s one in every family.

First, the media. Vanity Fair knows one thing: Sarah Palin moves magazines. They wouldn’t deign to interview her and give her a glowing report a la Obama. But, oh, they do so want to stay in business. With ad revenue down the crapper, how to use her for their own ends? It is inspiring that they at least seem somewhat market-driven. They recognize that pesky capitalistic cycle — supply and demand. So, there’s a silver lining.

However, it’s pathetic to interview this guy and portray his musings as fact. Any possibility of corroborating one thing he says? I somehow doubt family members are going to talk given the treatment they’ve all been subjected to. Some feel a little sympathy, but even some sympathetic journalists can’t dismiss Johnston outright. In typical relativistic fashion, this is Sarah Palin’s fault, according to Cynthia Tucker:

But the larger share of blame for this very public dysfunctional family saga has to be borne by grandma, Sarah Palin. She’s the person who introduced a young Levi to national celebrity. She’s the one who invited him to share the stage at the Republican National Convention, to campaign with her and Bristol, to share the adoration of the ultra-conservative base.

So he’s old enough to help his girlfriend make a decision to abort. He’s old enough to have insights about the long-time marriage of a couple with five kids. He is not old enough to decide whether to be in the spotlight.

Got it. He’s responsible and credible except when he’s not.