After Toronto van attack, Canadians mourn and ask simple question: Why?

After Toronto van attack, Canadians mourn and ask simple question: Why?  USA TODAY Motive still unknown after driver kills 10 pedestrians in Toronto  CNN Toronto van attack: How is the suspect not dead?  BBC News What we know about Alek Minassian, alleged driver in deadly Toronto van attack  CBC.ca Christie Blatchford: Deadly van attack can't divide Toronto's most diverse neighbourhood  National PostFull coverage