Sometimes Americans need a refresher course in the obvious.

In recent weeks, prominent conservatives have taken to the airwaves to identify racists that have flown under the radar. Talk radio hosts and politicians are particularly adept at spotting these elusive creatures.

According to these very perceptive white men, all wizened veterans of the civil rights movement, Judge Sonia Sotomayor is a racist. They insist that President Barack Obama's nominee for the U.S. Supreme Court is a racist at best and a "racialist" at the very least.

Even the black head of the Republican National Committee said that he feared that white men -- that despised and disadvantaged group -- couldn't expect justice from a Sotomayor court. The nexus of all racism in America, according to these experts, is a Latina woman sitting on the U.S. Supreme Court.

This is how the discussion proceeded for a few weeks -- fundamentally unserious and without meaningful consequence. Then a terrible thing happened in the nation's capital two days ago.

An 88-year-old white man burst into the lobby of a Jewish museum dedicated to the teaching of tolerance and shot a black security guard to death before being wounded by return fire from the guard's colleagues.

James Wenneker von Brunn was shot in the head, but clings to life. The man he murdered in a fit of inchoate racial rage was Stephen T. Johns, 39, a six-year veteran of the United States Holocaust Memorial Museum security staff.

For those silly enough to apply the tag "racist" to someone like Judge Sotomayor, Mr. von Brunn's attempted bloodbath at the Holocaust Museum is a teachable moment. They should pay attention to this.

Wearing a Confederate hat and carrying a .22 Winchester rifle, the alleged killer spent an inordinate amount of time on the Internet conversing with other people about how much he hated blacks and Jews before he strolled into the museum.

There are many things Mr. von Brunn doesn't believe. He doesn't believe the Holocaust ever happened. He doesn't believe America fought on the right side of World War II. He doesn't believe the right to keep guns is secure. He doesn't believe all men (and women) are created equal. He doesn't believe a white man has a chance to achieve anything in America anymore.

He doesn't believe Barack Obama is an American. According to notes found in his car, von Brunn believes the 44th president of the United States was created by Jews and is incapable of independent thought.

For those momentarily distracted by the silliness of talk radio, take a close look at the face of James Wenneker von Brunn. This is what an unreconstructed American racist looks like. His is the face that has been historically hidden behind white hoods and partially obscured by Nazi salutes. Every juror who has ever voted to exonerate a good old boy for doing what good old boys did to blacks with ropes and kindling wood will recognize his face. They've seen his reflection in their own mirrors for decades.

This is the face of a racist. Racists come in all colors, but in America, this is what a racist typically looks like. They spew a particular brand of rhetoric that has its roots in National Socialism and American racial paranoia. They appreciate fascism and outmoded theories of racial superiority. They confess their hatreds to anyone who will listen whether on the radio or online. They are terrified of anyone who is different. They are evangelists for intolerance and murder -- the more cowardly, the better.

I get e-mail and phone calls from people who are racist every day. They recognize von Brunn as someone who at least has the courage of his warped convictions.

Fortunately, whether they own a stockpile of weapons or not, most racists are cowards. They could never bring themselves to do what von Brunn did.

They'd rather fantasize about it and avoid the heavy lifting of fighting for what they truly believe in.

Meanwhile, they sit in their cars during rush hour or in their homes and work places every day, listening to cynical talk radio hosts telling them how oppressed they are by Latina judges and black presidents. They dream of confronting those who make them feel small and insignificant in their own skin. They are afraid of so many things.

This is the face of racism in America. It is as an old and familiar face.