The difference between the two countries is "choice". In Canada I CAN NOT carry a six shooter to the grocery store. In the USA I can IF I WANT TO (in most states as long as you follow the rules).
In the US I can purchase crappy government healthcare insurance for less than what I would pay in taxes in Canada IF I WANT TO. In Canada I HAVE to have crappy government healthcare insurance and can only get better insurance IF I WANT TO PAY FOR IT.
Choice ... it's a strange thing ... smells like, tastes like, and feels like ... freedom.
I think you hit upon something here and I just have to comment to add to your point.
The main cultural difference I see between the US and Canada comes down to where on the spectrum they fall between security and freedom. I would apply this to a lot of different peoples and countries as well, including across history.
Everyone wants both to feel safe and be provided for (security), while also wanting to feel like they control their own lives and destiny (freedom). History is really just the struggle between these two poles, because the problem is that you can't have fully one and the other at the same time.
Total security means you have no freedom. Imagine you lived in a prison cell, but all your meals and little creature comforts were provided for you. You were never in danger, never hungry, never cold, never afraid. But you could not leave, because doing so might put you at risk. That is total security.
Now imagine you lived in the wilderness, and every day was a struggle for survival. You could do whatever you wanted and go wherever you wanted, all simply limited by your own abilities, and nothing else. Fear, hunger, cold, conflict with others, was all part of life everyday, but you were free. Nobody to tell you what you can and can't do. That is total freedom.
Which is better? Both extremes have obvious drawbacks, so we strive for some kind of happy medium, but a perfect balance is very hard to achieve, so we inevitably tend toward one more than the other.
I would argue that Canadians, as a whole, err toward the side of security. While Americans, as a whole, err toward the side of freedom.
I, for one, would rather err toward freedom. I would rather face some risk and uncertainty in life, rather than feel too constrained. Freedom is more important to me than security, because I would rather face fears than be ruled by them. And probably most Americans agree with me, but most Canadians believe the opposite, and thus the difference in the two countries' respective cultures, and downstream from that, in their politics and governments.
Which side of politics a person ends up on usually comes down to this question then: Given a choice, what is more important to you: Security or Freedom?