Update on our home-grown terror movement...
The Earth Liberation Front.
Of course, their website, complete with terror manual, is old news to most of us who follow such things, and has been proudly displayed for at least a couple of years. Not surprisingly, considering their politics, they don't get the grief from the media and others that some others might get for this sort of thing (think militias).
Like Al Quaeda, the ELF takes advantage of a highly decentralized structure.