The slaying of six people at a Sikh temple by a gunman with ties to white supremacists has raised questions about the scope of domestic terrorism — and what law enforcement is doing to stop it.
Federal law enforcement agencies cracked down hard on homegrown extremists after the 1995 Oklahoma City bombing, which killed 168 people, including 19 children at a day care center. Many leaders went to prison, died or went bankrupt.
But in recent years, the spread of the Internet, the worsening economy and changing demographic patterns have been giving new voice to hate groups.
White supremacists are generally motivated by a desire to separate themselves from people of other races — and deep fears that they are losing ground. No one keeps track of exactly how many there are. But the Southern Poverty Law Center, which studies hate movements, estimated there were at least 133 racist skinhead clusters inside the United States last year.
The Anti-Defamation League, which also closely follows extremists, reports that Wisconsin shooter Wade Michael Page had been a member of the Hammerskin Nation, the most violent and well-organized of the white supremacist groups. Prospective members undergo a probationary period, pay dues to the organization and pledge their loyalty.
It's such a serious promise, according to Mark Potok of the SPLC, that Hammerskin members have been known to hunt down defectors and cut the white power tattoos from their bodies.
There's no clear definition of domestic terrorism, but a May 2012 report by the Congressional Research Service suggests that law enforcement uses the term to describe extremists in the U.S. who are motivated by ideology but without strong ties to an overseas group. The U.S. government doesn't formally designate domestic extremist groups, unlike foreign terrorist organizations such as al-Qaida.
But there's plenty of evidence that American-grown haters can get access to lethal materials and deploy them inside U.S. borders. Late last year, Kevin Harpham was sentenced to spend 32 years in prison for his role in planting a sophisticated backpack bomb along a Martin Luther King Jr. Day parade route in Spokane, Wash. The bomb, studded with nails designed to blow in every direction, was discovered shortly before the start of the festivities. The FBI said Harpham had contact with neo-Nazi organizations.
And in February of this year, Jeffrey Harbin of Arizona was sentenced to prison after he pleaded guilty to transporting improvised explosive devices — including homemade grenades and pipe bombs he allegedly made using model rocket engines — along the southwest border with Mexico. Researchers say Harbin was a member of the neo-Nazi National Socialist Movement.
Analysts like Potok and agents at the FBI and the Bureau of Alcohol, Tobacco, Firearms and Explosives increasingly are sounding the alarm about sovereign citizen groups, too. They're called that because they refuse to recognize the authority of the government, by failing to pay taxes or register for driver's licenses.
But in the most extreme cases, sovereign citizens have lashed out at, and even killed, law enforcement officers who have pulled them over at traffic stops or for minor violations of the law. Two police officers in West Memphis, Ark., died that way in May 2010.
If nothing else, the Wisconsin shooting has reignited a conversation about whether police, Congress and reporters should pay as much attention to domestic threats as the ones coming from Afghanistan, Yemen and elsewhere in the years after the Sept. 11, 2001, attacks.
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