the US and Canada have been allies continually since Canadian confederation in 1867, and are now adversaries if not enemies for the first and only time.

Neither adversaries nor enemies.
Just a squabble between neighbors.

"Canada and the US have a highly integrated and extensive trade relationship, with the US being Canada's largest export market and Canada being the US's third-largest source of imports. In 2024, Canada exported roughly 76% of its goods to the US, and imported almost half of its goods from the US."

"U.S. total goods trade with Canada was an estimated $762.1 billion in 2024. U.S. goods exports to Canada in 2024 were $349.4 billion."

"The United States was the sole export market for nearly two-thirds (65.9%) of Canadian exporting enterprises in 2024."

This is unlikely to change majorly.

For Canada, trade with the US is just moving products a hundred or less miles via truck or rail car. Before lunchtime. Across a order that is 5,525 miles, through about 120 ports of entry.
Whereas trade with any other country has to go by ocean ship. After traveling inside Canada for average 2,600 miles to either coast. Through the bottleneck of just 5 major seaports.

None of that means that the US wants to make Canada a state. That's just bogyman thinking. And -- no offense -- Canadians puffing themselves up.

Canada is getting slapped right now because America thinks that they have been annoyingly taking advantage of the cross-border trade. (And it is not just Trump.)