After Earth's Climate Collapse, Canada found itself with and an enormous influx of climate refugees. This and the collapse of United States of America put massive pressure on Canada to handle not just a climate crisis but a war-torn neighbor whose violence often boiled over the borders. The country barely survived intact, and lost swathes of territory (secessions of Toronto Free State, Quebec & Cascadian Secession).
After things stabilized politically, Canada recovered quickly. It was now in possession of the largest body of arable and uncultivated land on the planet, newly temperate due to climate change. Its northern shipping lanes were now free of dangerous ice and newly passable. It had an enormous immigrant population ready to rebuild a prosperous society.
Now, Canada is beginning to throw its weight around politically. It has been clashing a bit with Minneapolis Motor Syndicate, and likely has the means to crush it completely. And there is a strong revanchist movement in the government that seeks to recapture seceded territories, though such measures are relatively unpopular.