fear is a legitimate response to threats
fear-mongering CAN be used as a propaganda device
fear is also what terrorist organizations seek to create through mass casualty attacks and high profile murders
the whole point of critical thinking is to understand whether you are being manipulated or whether you are the target of an extremist organization; and then how to respond to that situation
both words and laws can be used as weapons, as you stated. It is best to think HOW to use these weapons effectively