If you live in the Delaware Valley, you've surely heard about the brutal December attacks on Asian students at South Philadelphia High School. Seven kids were hospitalized with injuries sustained mostly at the hands of African American students, who beat Asians in classrooms, hallways, the cafeteria, and the streets outside the school.

But the incident has barely registered outside the area. To understand why, try a small thought experiment: Imagine if the victims were black and the attackers were white.

The whole nation - indeed, the whole world - would know. The president would denounce the episode on television and demand a speedy remedy. Members of Congress would eagerly join in, competing with each other to condemn the racism in our midst. And hordes of reporters would descend on the school.

But, hey, they're only Asian kids getting beaten. And the attackers are black; we don't expect a whole lot from them anyway.

There's plenty of racism to go around here, and it's not just at South Philadelphia High. It's all around us, in the bigoted double standards we use to judge events like this.

Sadly, the behavior of African American students involved in the melee fits neatly into media-fed stereotypes of black hoodlums, drug dealers, and gangbangers. We see these images wherever we look, from movies and TV dramas to advertisements and music videos. So if we see it in real life, we shrug; it's what "they" do.

Most don't, of course. Yet when we refrain from criticizing black troublemakers as loudly as we do miscreants of other races, we reinforce the idea that African Americans are somehow prone to such acts. What could be more racist than that?

Ditto for our tepid reaction to the injuries inflicted on Asian kids. If they had been black, and the attackers white, we would have witnessed a national outpouring of concern for the victims. For centuries, African Americans have endured violence and vitriol at the hands of white people, we'd say. And now this.

News flash: Asians have suffered their share of hatred in America, too. We don't know or talk about it as much. But it's true, and pretending otherwise shows another stark racial inconsistency.

In the West especially, Asian immigrants encountered rabid prejudice and brutality. White mobs in Los Angeles hanged, shot, and burned 21 Chinese residents in 1871. Nine years later, another mob destroyed most of Denver's Chinatown. In Wyoming, whites killed 28 Chinese railroad workers; in Oregon, they murdered and mutilated the bodies of 31 Chinese miners.

Congress responded with a series of measures to keep Asians off our shores. In 1882, it prohibited Chinese workers from immigrating; a 1907 agreement with Japan effectively barred laborers from that country, too.

The states instituted their own discrimination. In California, a 1913 law prohibited Japanese immigrants from owning land. "All about us the Asiatics are gaining a foothold," warned one supporter of the measure. "It is a germ of the mightiest problem that ever faced this state, a problem that will make the black problem of the South look white."

During the Second World War, 120,000 Japanese Americans would be interned in concentration camps. Defending the current detention of accused terrorists at Guantánamo Bay, some contemporary conservatives have tried to justify the Japanese internment as a necessary war measure. But racism was at its core. "A Jap's a Jap," West Coast military commander John DeWitt declared in 1943. "The Japanese race is an enemy race."

After the 1970s, as Asians developed businesses in America's inner cities, African Americans became the latest entry on a long list of tormentors. Across urban America, blacks accosted Asians with taunts of "ching chong," "chow mein," and other slurs. Rapper Ice Cube denounced "Oriental one-penny-counting" Korean shopkeepers in a 1991 song, warning Koreans to "pay respect to the black fist" or "we'll burn your store right down to a crisp."

The same mix of violence and prejudice was on display at South Philadelphia High long before the December attacks. In 2008-09 alone, a legal complaint alleges, Asian students suffered 26 separate assaults at the school, mostly at the hands of African Americans.

But the school district's recent report on the melee makes no mention of this ugly past, providing an apt metaphor for our shared racial blind spots.

It's high time we held African Americans to the same moral standards as everyone else, lest we confirm the worst stereotypes of recent history. And it's also time we acknowledged that Asian Americans have a history, full of anguish and - yes - discrimination. Anything less will yield more of the same.