I'm not a Canadian, and what's more I'm old enougfh to remember WW II well.
I have no idea what percentage of the Japanese were actually interned and opposed to just being removed from the exclusion zone.
What caused FDR to decide on exclusion from the West Coast was the fact that in every country which the Japanese conquered an occupation government immediately emerged from among the Japanese expatriates there.
To him that indicated a very thorough penetration of the Japanese diaspora by Japanese intelligence.
I understand his thoughts and the reasons for it. Check out the above link though. There were not 120,000 "hard cases". Imagine your government doing this to you. I have friends who lost everything. The fact the policy was reversed in two years tells you they realized it was a big mistake.