To Kill a Mockingbird is one of the great American books that became an equally great movie. So it was fitting that President Obama held a showing of the film at the White House, with Veronique Peck, whose late husband Gregory Peck played the heroic, small-town lawyer, Atticus Finch, in attendance.

But I couldn’t help thinking, when I heard about the evening: Oh, dear.

As I suspected he might, President Obama reportedly used the occasion to promote (false) comparisons of the situation in the movie, which revolves around an innocent black man accused of rape and his lawyer's valiant attempt to win his freedom,with the current tragedy of the shooting of young Trayvon Martin. It’s always proper to see the relevance of art for our contemporary situation. But we should be careful to get the analogies right.

The Guardian newspaper headlined its story on the showing as “Obama as Atticus Finch.” I can't help thinking that the president's initial response, saying that, if he had a son, he would look like Trayvon, fanned the fires of racial hatred. Atticus Finch would have refrained from doing this. Atticus, unlike the president, also took a lonely stand that didn't contribute to his being re-elected to office.

William McGurn shows how phony the comparison is in a piece in today’s Wall Street Journal:

Where's the presumption of innocence, which in the novel was denied Tom Robinson, the black man falsely accused of raping a white woman? Perhaps it was denied Trayvon Martin, who, so far as we know, had nothing more menacing on him than a bag of Skittles when he was killed. Or perhaps it is the shooter George Zimmerman, who is now in hiding because so many want not justice but his head?

Who is the Walter Cunningham here—the hard-working white farmer who seems decent enough but nonetheless accompanies a lynch mob to the Maycomb, Ala., jail? Might it be Spike Lee, the filmmaker who in the midst of escalating racial tensions tweeted out what he thought was Mr. Zimmerman's address. As it turned out, Mr. Lee had the wrong Zimmermans, but would Atticus have thought it any better had he had the right ones?

Or what about the novel's newspaper editor, Mr. Underwood, who in a scathing editorial indicts white Maycomb by comparing Tom Robinson's death "to the senseless slaughter of songbirds." Would this be NBC, which edited a 911 tape that made the accused appear as though he was offering up a comment on race when he was in fact responding to a question from the police dispatcher?

Where, above all, is Atticus Finch? Is it the Rev. Al Sharpton, who shares with Mayella Ewell a phony charge of sexual assault—in his case, falsely accusing a white assistant district attorney of having raped a teenaged Tawana Brawley? Is it the Rev. Jesse Jackson, who once spoke about the anxiety he felt when he heard footsteps approaching him from behind—and the relief at turning around and seeing "somebody white"? Or the Rev. C.L. Bryant, a former NAACP leader who like Atticus Finch believes that justice is something for the courts and accuses the Revs. Sharpton and Jackson of being "race hustlers"?

We don’t know what justice in this case will be: did George Zimmerman shoot Trayvon Martin in cold blood, or was he attacked and fired on the youth in self-defense? My friend Maggie Gallagher says that Zimmerman should have been arrested by now and that this case must be decided by a trial. I can’t help thinking that, at the very least, Zimmerman is not exactly the sort of guy who should have been an armed member of the neighborhood watch. But the important thing, as Atticus Finch would have known, is justice—for Trayvon and, yes, for George Zimmerman. We don’t know what that is for Zimmerman (being unconflicted about the death penalty, I have no problem with the ultimate penalty, if he shot Trayvon in cold blood), but let’s hope that the legal system will get at the truth, in a way that it didn’t in To Kill a Mockingbird.

The unfortunate truth is that we have a mob now, just as there was in the movie, baying for blood.