If we're not going to police our own, the opposition can define us any way they choose.

A President Obama impersonator was pulled off the stage Saturday at the Republican Leadership Conference, after telling a string of racially themed jokes about the president.

The impersonator, Reggie Brown, took the stage at the annual presidential cattle call to the Bruce Springsteen song "Born in the USA" -- an apparent allusion to the birther controversy. He proceeded to tell a series of off-color jokes poking fun at Obama's biracial heritage and a gay member of Congress. (See the video here.)

Eventually, RLC President and CEO Charlie Davis made the decision to pull him offstage, and a man came onstage to physcially escort Brown off.

"I pulled him off the stage," Davis acknowledged afterward. "I just thought he had gone too far. He was funny the first 10 or 15 minutes, but it was inappropriate, it was getting ridiculous."

I am all for ridiculing President Obama. He's an easy target for that what with his record of incompetence, naivete, and stupidity.

But this goes way too far:

On Black History Month: "Michelle celebrates the full month. I celebrate half."

• "My mother loved a black man," but "she was not a Kardashian."

• A picture was shown of Obama and the first lady when he took office. The impersonator then showed a picture of what the Obamas will look like when the president leaves office, and it was the characters of Fred Sanford and his sister-in-law, Ethel, from the show "Sanford and Son."

Race wasn't the only subject where the impersonator pushed the envelope.

• Of Tim Pawlenty's decision not to criticize Mitt Romney at Monday's debate: "[CNN's] John King served him up a ball softer than Barney Frank's backside." (Frank is a gay member of Congress from Massachusetts.)

• Of Newt Gingrich's approval ratings: Dropping "faster than Anthony Weiner's pants in an AOL chat room."

• There was also one moment where the original Weiner twitpic was shown on the large screens on either side of the impersonator, with no blurring.

This is not a question of political correctness. It is a question of taste and racial stereotyping. (Note: the Weiner jokes were funny, but the venue was inappropriate). By the time they got this lout off the stage, the damage had already been done.

Handing your opponent a weapon with which to knock your brains out is stupid politics. Besides that, it demonstrates an extraordinary insensitivity to allow this sort of thing at an official party gathering.

Society draws lines when it comes to humor. Those lines were crossed at this event.