Define "feel threatened".
Should one person or group of people be able to literally threaten another? No.
Should people be able to express their views on social issues and policies? Yep. If that makes others feel uncomfortable, that's their problem.
That sounds fine in principle, but reality is different: there is only so much ill will that humans are able to accomodate for before they break down and resort to some form of aggression or dysfunctional behavior (physical violence, drugs, ...).
The whole society then suffers from that.