by Jo Thomas

About the author: Jo Thomas is a reporter for the New York Times.

After the 1995 Oklahoma City bombing, law enforcement officials began struggling with a big unanswered question: Were domestic terrorist attacks by white supremacists, both actual and thwarted, isolated events, or the work of a cohesive underground movement"

Federal and state investigators, including undercover agents, have painstakingly searched the evidence in a growing list of bombings, shootings and robberies. But they maintain that there is no evidence of an organized effort among the disparate assortment of violent right-wing groups and individuals scattered across the country.

Leaderless Resistance

Instead, top-level law enforcement officials and experts on terrorism say, what has emerged is a new style of "leaderless resistance"—long urged by white supremacist leaders—of very small cells, pairs or individuals, called...