In a moment of extreme clarity here in Canada, an RCMP (Mounties) officer answered criticism from the public and media about the fact that prior to a recent "terrorist" incident there was evidence that one of the perpetrators had expressed anger publicly over something that "should have been picked up by the security services".
The officer's response was something along the lines of (and I paraphrase here) "there was unsufficient evidence of this leading to the atrocity that was committed and, contrary to what some people believe, it is not a crime to be angry or have unsavoury opinions in this country."
I just wish more people would realise that this is the proper response to this kind of situation.