Rudeness at any age is an ugly thing.

But from a 61-year-old TV host who prides himself on being a champion for working class Americans, it’s especially jarring.

As Day 2 got underway in Washington, D.C. Federal Court, it turns out MSNBC’s Ed Schultz is the Naomi Campbell of the media industry — who knew there was a diva living inside that giant head and portly body? (A refresher course on Campbell: the supermodel once hit her maid in the head with a cell phone.)

Judge Beryl Howell, an Obama appointee, began the day by giving Schultz a spanking for being rude to members of her courtroom staff. The Mirror is still digging for details on specifics, but suffice it to say that Schultz hasn’t made a good impression.

“Your client is a star, but not with this staff,” Howell railed at the host’s lead attorney John Hayes just after 9 a.m. Tuesday morning.

Schultz is being sued by NBC producer and sound engineer Michael Queen for breach of partnership. Queen says he helped Schultz land his MSNBC show. Schultz boasts that his 30 years in the business got him his job.

Howell seethed, “Arrogance is noticed by the jury and it’s noticed by my staff. I won’t have my staff treated discourteously. He may treat others discourteously, but not my staff.”

She angrily asked Hayes to please instruct his client to get the memo and behave appropriately.

Oh. He got it. As the judge went off, Schultz sat at a courtroom table still and stoic. No one on his stand of the case seemed to know how to react to the rudeness charge.

The Mirror can attest to Schultz’s lack of basic manners. During the pre-trial hearing when I asked him a question, he replied with a huge eye roll and walked away from me in a huff. Even the security guard laughed at his response.

As we were all filing into the courtroom today, I happened to be walking behind Schultz and his entourage — his attorneys, his wife, Wendy, and their friend, Connie, who gives Schultz brief hugs of encouragement any chance she gets. Mind you, there were two sets of doors. While he held the doors for his posse, he let them fall for me — twice.

Later in the day, my cohort Evan Gahr held the courtroom door wide open for Schultz, who didn’t so much as nod for the gesture as he walked right on through.

Granted, Schultz doesn’t seem to have great affection for the reporters covering his trial.

But he could at least practice basic politeness.