There are intertwined issues here.  From all reports, Mr. Christian was a right-wing unhinged individual who killed two men (and seriously wounded another) who attempted to intercede as he accosted two young women.  Clearly he was shouting anti-Muslim comments as he did so.

The "Trump Free Speech" issue is really quite separate.  IMO, it will attract hard-core right-wing activists to Portland.  It will likely also energize hard-core left-wing activists to oppose it.  These are two groups with little restraint regarding physical violence.  I think it's highly likely that "street demonstrations" will get quite ugly.  

That said, I am a strong advocate for First Amendment rights.. Like the ACLU and their defense of the American Nazi Party's march in Skokie, Illinois, I defend the Trump folks' right to hold an event in Portland.  

I would suggest two things to Mr. Wheeler: a) have a very strong police presence and b) if possible, forbid the wearing of barclavas and masks.  Gary Crum