Timothy McVeigh got his start watching Waco burn, hanging out with groups around the US "militia movement", and reading The Turner Diaries, and had like 3 accomplices.

He wasn't a "lone wolf".

But he also wasn't actually acting as a part of anything like the Red Brigades either, so the GP's point still stands.

https://www.simonandschuster.com/books/Blowback/Margaret-Rob...