Editor's note: David Frum writes a weekly column for CNN.com. A special assistant to President George W. Bush in 2001-02, he is the author of six books, including "Comeback: Conservatism That Can Win Again," and is the editor of FrumForum.
(CNN) -- Which American politician of the past 25 years has had the most lasting influence? Ronald Reagan, with his vision of low taxes and limited government? The triangulating Bill Clinton? More and more I'm beginning to fear: It's Al Sharpton.
The Reverend Al, as the New York tabloids used to call him, had a genius for inventing ethnic conflict.
In the 1990s, he and his allies would frame incidents in ways brilliantly calculated to set New York's ethnic populations at each other's throats. New York became a theater of grievance. Everyone -- blacks, Korean-Americans, Jews, Italian-Americans, cops -- could feel himself or herself victimized at the hands of somebody else.
It was Sharpton who championed Tawana Brawley's false claims of gang rape -- and who accused investigators who doubted her claims of racial bias. When a complex dispute over tenancy at a Harlem store ignited protests, Sharpton was there to incite the protesters with denunciations of "white interlopers." The protests eventually culminated in a shooting rampage and firebombing that killed seven store employees. After that incident, Sharpton began work on changing his image. He lost weight, bought tailored clothes, launched a radio show and ran for president.
But the methods that once enflamed a single metropolis can now convulse our global village. A Danish imam seizes upon cartoons in a Copenhagen newspaper to incite rage in the Middle East. A New York religious entrepreneur proposes to build a mosque near ground zero, generating a fierce negative reaction among American conservatives. A pastor in Gainesville, Florida, threatens to burn copies of the Quran, sparking fears of violence in Afghanistan.
All these years later, the methods that once ignited Crown Heights or Harlem resonate across the planet. Create an incident -- generate howls of anger -- generate counter-howls of counter-anger. Rinse. Repeat.
The secret to success is to frame a scenario in which all parties can see themselves as victims of powerful enemies. Offended Muslims can see themselves buffeted by outbursts of intolerance: first the Lower Manhattan mosque controversy, now the Quran-burning. But offended non-Muslims can also see themselves as victims. It's legal to burn the Bible isn't it? Or the American flag? Would President Obama ever have a member of his Cabinet telephone and ask a flag-burner to cease and desist? Of course not. So why is the Quran protected by political correctness? What's so special about their book? Do Muslims gain extra rights because we fear they will be extra violent?
It's brilliant isn't it? You can be obscure, but if you invent the right provocation, you will not be ignored. Your manipulation of the media may be obvious -- yet the media cannot resist. The same media event leaves Muslims feeling they are uniquely singled out for attack -- and non-Muslims feeling that Muslims are uniquely singled out for special consideration.
Then, next move: You don't burn the Quran! Instead, you deplore provocation, speak of brotherhood, announce you are available to meet with your opposite numbers. Invoke Gandhi and Martin Luther King. Now you have mellowed into a peacemaker. Who better than you to heal the rifts that nobody now remembers you yourself exploited in the first place?
The user manual is available to all. It worked in New York City. Now it works globally. Who will try next?
The opinions expressed in this commentary are solely those of David Frum.