Seriously though,
While I am not saying that Canada would never be the target of a terrorist attack, the chances are slim. It is much more likely that Canada would be used as a staging ground for terrorist attacks against the US. This argument has been made numerous times. Our proximity to the US, the rather porous nature of our borders, our lax border control and immigration policies and our large immigrant populations, the availability of useful off-the-shelf technologies etc. make Canada an ideal staging point where terrorists can blend in quite easily.
After the US, Canada has more terrorist organizations operating within its borders then any other country in the world (Accoding to CSIS).
Everyone remembers Ahmed Ressam...
Something to consider...