Story highlights Twenty years ago, on April 19, 1995, Timothy McVeigh set off a massive bomb in Oklahoma City

Deborah Lauter and Mark Pitcavage: Right-wing extremism should still be taken seriously

Deborah M. Lauter is director of civil rights at the Anti-Defamation League. Dr. Mark Pitcavage, an expert in right-wing extremism, is director of ADL's Center on Extremism. The opinions expressed in this commentary are solely those of the author.

(CNN) Twenty years ago, on April 19, 1995, Timothy McVeigh detonated a massive truck bomb in front of the Murrah Federal Building in Oklahoma City. The attack killed 168 men, women and children, injured hundreds more, and remains the deadliest act of domestic terrorism in U.S. history.

The attack's aftermath saw a storm of media coverage with themes such as "attack on the heartland" and America's "lost innocence." In fact, the bombing took the country by surprise. It wasn't simply the scale of the tragedy that drew attention, but the fact that the bombing exposed something new: American citizens targeting their own government with a deadliness hitherto unseen.

Deborah M. Lauter

Mark Pitcavage

The public became aware of the true danger of the extreme right. Reports connected McVeigh and his accomplice Terry Nichols to anti-government ideology movements, such as the militia movement, as well as to white supremacist causes.

Law enforcement also played catchup. The Federal Bureau of Investigation's 1994 annual report on terrorism had given short shrift to the extreme right. Its coverage of domestic terrorism focused on the activities of Puerto Rican radicals and animal rights and environmental extremists.

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In contrast, the report spent only a paragraph describing the threat from right-wing extremists. It ignored the rapidly growing militia and sovereign citizen movements, and made no reference to events in Idaho and Texas.

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