WASHINGTON -- Political terrorism, exemplified by 9/11 and most recently in London, may pose the greatest security threat facing most nations. But other terrorists also lurk among us, mostly in the guise of animal rights and environmental activists.

They "see themselves in a war against the entire government and industrial democracy itself," explains Mark Potok, director of the Southern Poverty Law Center's Intelligence Project. Frankie Trull, president of the Foundation for Biomedical Research, notes: "These are unbelievably mean-spirited people" who "operate in a classic terrorist organization mode."

Over the last decade the Animal Liberation Front has committed 700 criminal acts in America, according to the FBI. ALF activists recently broke into a pharmaceutical executive's wife's car, stole her credit cards, and charged $20,000 in charitable "donations."