The primary difference between Canada and the US was that Canada was small/smart/lucky enough to enact some social nets before the world became too easy to manipulate by media and the internet.
I would say it would it comes down to a much healthier government with more churn and not two different flavours of the same political party. I only found out this year that in certain states the ballots contain options "Vote all Democrat" or "Vote all Republican". Enshrining political parties like that into an electoral process reminds of the Soviet Union.
So what we have now is that some countries ossified after passing lots of welfare systems while others ossified before. The ones where welfare is present end up serving a higher quality of life for its lowest ladder of folk, ensuring a better scenario for them to not radicalize much (just comparatively, look at France).