Using your reasoning, I could point to clear examples of why you should be afraid of Canadians, or Americans, or Hindus, or any other group you wish. That's because no identifiable group of people is free of those who do harm. But it's not rational to be afraid of Canadians, or to be afraid of any other group based on their race, religion, gender, etc. It's completely irrational, because by and large the overwhelming majority of all humans are peaceful and law-abiding.

By all means, fear a hate-filled person that's shooting people in cold blood. But don't if you fear all Canadians because one of our number just perpetrated that horrific crime, you are showing evidence of a phobia, and irrational fear of Canadians.