I told him I was sorry he had to put up with her behaviour. What I didn't say, but implied, was I was sorry he was treated like a lesser person for no other reason he looked different and was possibly an immigrant.

On an even deeper unconscious level, I was probably apologising on behalf of most Canadians who accept (if not embrace) people of racial and cultural diversity.

The reason he didn't respond wasn't because of something I said. We were both kind of gobsmacked at what happened.