Sci-fi writer CJ Cherryh perfectly summed up my view on this (thus saving me some typing and likely being more succinct than I tend to me):

"This death by political violence wounds the left as much as the right. Silencing a speaker by violence and assassination is the antithesis of the world liberals would wish to see --- and much as I strongly oppose his views, I mourn for our national tradition of free exchange of ideas, mine, yours, his, and everybody's. Freedom took a body blow today."