- Christopher Lee Cornell, 20, allegedly aligned himself with ISIS
- A source says the plan posed no threat to lawmakers; the complaint said it was in its late stages
- "If I thought he was up to something, I would have beat his butt," father says
(CNN)For months, 20-year-old Christopher Lee Cornell had been on the FBI's radar. Authorities said he left alarming posts on social media, talking about violent jihad.