What Drives Anti-Government Extremists

The horrendous ambush assassination of two Las Vegas police officers at a pizzeria and the killing of a good Samaritan by a violent young married couple with anti-government hatred again show that domestic extremists on the fringes remain a continuing threat in America.

In fact, in recent weeks the Department of Justice reconstituted a law enforcement working group devoted to addressing right-wing extremism. One of Sunday's killers, who was reportedly removed by other militia protesters from the Bundy ranch standoff earlier this spring, draped an officer's body with a yellow Gadsden "Don't Tread on Me Flag," a swastika and a note about "revolution."

In the 1970s, a significant violent threat came from small, tight-knit groups of the "revolutionary left" such as the Weather Underground and Symbionese Liberation Army as well as the anti-police Black Liberation Army whose assassination sprees left 13 officers dead across the nation.

Since the early 1980s, however, the domestic extremism threat pendulum has swung right...

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Note: Professor Brian Levin, a former NYPD officer and Stanford Law graduate has testified before Congress on right wing extremism and has advised federal and local authorities for over two decades. He is co-author of The Limits of Dissent, and is director of California State University San Bernardino's Center for the Study of Hate & Extremism.