well i guess you can thank Bush and the republican congress of 2001 for FBI involvement in such matters
Section 802 of the USA PATRIOT Act (Pub. L. No. 107-52) expanded the definition of terrorism to cover ""domestic,"" as opposed to international, terrorism. A person engages in domestic terrorism if they do an act "dangerous to human life" that is a violation of the criminal laws of a state or the United States, if the act appears to be intended to: (i) intimidate or coerce a civilian population; (ii) influence the policy of a government by intimidation or coercion; or (iii) to affect the conduct of a government by mass destruction, assassination or kidnapping. Additionally, the acts have to occur primarily within the territorial jurisdiction of the United States