Well, don’t say she hasn’t been warned.

Sarah Palin cannot make even one mistake in Thursday’s debate or she will be cooked.

George Stephanopoulos said so Monday on ABC’s Good Morning America:

Picking up on what Kevin Madden said in David Wright’s piece: Number one for Sarah Palin, she cannot make a mistake. A major mistake particularly on foreign policy would be absolutely fatal to her candidacy.

Good Morning America, like NBC’s Today Show and CBS’ The Early Show, played clips of Tina Fey doing her mocking impersonation of Palin on Saturday Night Live. When did comic impersonations become news?

And what about Palin’s opponent, Joe Biden? What if he makes a gaffe, as he is wont to do? Last week, Biden said in a speech that, “When the stock market crashed, Franklin D. Roosevelt got on the television” to calm the nation. The stock market crashed in 1929, before TV and before Roosevelt was president.

No problem. The liberal media have Joe’s back and won’t make a big deal of it. Palin made no notable errors last week, yet she was still the one to be savaged. It’s a pity Saturday Night Live can’t remove their ideological blinders. What a great skit Biden might have inspired! Imagine Bill Murray coming back to portray Biden: “It’s just like when George Washington climbed up on a tank to rally the troops at Gettysburg…”

Back to reality. During Thursday’s debate, the press will be listening so hard for a Palin version of “macaca” that they probably won’t even hear what Joe has to say.

“Macaca” was the word that helped sink the re-election campaign of Virginia Republican Sen. George Allen in 2006. He had used the word, which means “monkey” in some African nations, jokingly to describe a Democratic operative tracking his campaign events. Allen said his mother used to call him that when he messed up, the equivalent of “rascal.” No matter. The media decided that because the Democratic staffer was of Indian ancestry, macaca was an openly racist term, just the thing a sitting U.S. Senator would say in a racially diverse state like Virginia. The Washington Post in particular beat up Allen with macaca for the next month, using the term dozens of times. Allen never recovered and Jim Webb narrowly won his Senate seat.

Here’s the rule of thumb:. When a liberal misspeaks, it’s a slip of the tongue. We all make mistakes. If you are a conservative, however, you commit an unforgiveable sin that must be revisited a thousand times until you are out of Purgatory – or office, whichever comes first.

On Friday, Barack Obama made two mistakes that the media would have used to crucify McCain had he made similar errors.

First, Obama misstated that Henry Kissinger would support meeting enemies like Mahmoud Ahmadinejad without preconditions. Even when McCain corrected him, Obama repeated the point. Immediately after the debate, Kissinger issued a statement that rebutted Obama in no uncertain terms. Gotcha! The media’s reaction? Snore. Bury that sucker in reams of copy.

Another suitable moment for carving into a media bat came after John McCain showed his metal bracelet worn in memory of Cpl. Matthew Stanley, who was killed in Iraq. Obama noted that he, too, wore a bracelet for a fallen soldier. Then he forgot the name of Sgt. Ryan David Jopek and had to look down and read it.

It’s not awful, and could happen to anyone, but can anyone honestly imagine that the media would have ignored this had McCain been the forgetful one? Another wrinkle: Jopek’s mother, an Obama supporter who had given him the bracelet, had e-mailed the Obama campaign and asked Obama not to use her son’s name in either speeches or debates. As Newsbusters’ Warner Todd Huston reported, the AP said Sunday that she had, indeed, asked him not to do this, but had been okay with how Obama presented it during the televised debate. Again, imagine what the media would have done had McCain been asked by a parent not to invoke a deceased son’s name and then done so?

CMI just released a new special report, ‘Character’ the Most Important Issue in the Presidential Primary Debates. One striking finding was that the media asked the Democrats nearly twice as many “softball” questions as they asked Republicans. Republicans got 25 percent softballs, Democrats 48 percent.

Being a liberal in a political campaign is a bit like being a cornerback in a fixed football game. He can take cheap shots at receivers all day, knowing the referees will never call him on it. On the other side of the ball, the quarterback can throw all bombs he wants, knowing that if one is picked off, the refs will find a way to nullify the play.

Keep in mind that the moderator for Thursday’s debate is PBS’s Gwen Ifill, who has just written a pro-Obama book, The Breakthrough: Politics and Race in the Age of Obama. As Michelle Malkin notes on her Website, the book’s promo says Ifill is “introducing the emerging young African American politicians forging a bold new path to political power.”

Meanwhile the scribes are sharpening their poison pens and polishing their gun sights, otherwise known as cameras. They’ll be ready to draw more blood from Mrs. Palin than a bite from an Alaskan mosquito.

As for Joe, he can take comfort in the knowledge that his next gaffe won’t have a long shelf life, and that he can sit back, Biden his time.