What makes you say "certainly," especially in the hypothetical scenario where the US is unstable? Canada has a relatively much shorter history as an independent nation. Canada heavily benefits from its southern neighbor, and has a host of domestic economic issues (low wages, high housing prices; whatever the farmers are on about) that could cause instability as well. I think Canada is reasonably stable, I just quibble with "certainly" and "more" politically stable as compared with the US.

Canada is more internally stable, but is less externally stable, given that invasion and occupation is on the table.

Canada needs to pursue further armament (Carney is pursuing a doubling of its defense budget) and training in asymmetrical warfare.

All historically-stable Western nations seem to be subject to the same influences that brought us Trump, though.

They (we) are all under attack.