Possible Clues:

• Person who uses violence for political purposes, such as member of Al Qaeda
• Rotter, sir! (anag.)
• What frightful behaviour one is guilty of
• Insurgent's mistake is getting introduced to extreme characters in Tibet
• Political warrior
• Killer's mistake is to interrupt races
• Is tense after naughty child becomes radical
• Villain in many an action movie
• Radical mistake one's found in empty threat
• Many an action movie villain