The slaying of six people at a Sikh temple in Wisconsin 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, NPR reports. Federal law enforcement 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. 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. The Southern Poverty Law Center estimated at least 133 racist skinhead clusters in the U.S. last year. American-grown haters can get access to lethal materials and deploy them inside U.S. borders. 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. This year, Jeffrey Harbin of Arizona was sentenced to prison for transporting improvised explosive devices — including homemade grenades and pipe bombs he allegedly made using model rocket engines — along the southwest border with Mexico.