You are correct in pointing out that it doesn't have much to do with the rest of my argument. I posed it as a question because I think a lot of the opinions around this issue (like many or most issues) stem from emotions. In this case I think this argument comes from a sense of fairness: motorists have to pay tax / have insurance / pass a test; so why shouldn't cyclists? I think if you consider whether we would even be asking that question if there were no motorists, you can get around the "fairness" point of view.

Interesting. I wasn't coming from that angle. I think cycling would be less risky if there weren't cars on the road, so I would see less of a reason to have cyclists take a test and get a license if they didn't have to mix with auto traffic.