All my adult life Canada and the US have had trade friction.
The US is going through a phase which is unlikely to outlast Trump's tenure. Dissatisfied voters have pushed back by electing a president who pushes everything. There are simply too many people who will jettison tariffs at the first opportunity, including - probably - whoever is the next president, no matter what some of them are saying (or not saying) right now just to avoid being passed under the harrow. And I expect tariffs to end much sooner than that, because voters and established interests won't tolerate the fiscal pressure for that long.
Every minute people spend tearing their hair out over Trump's latest ridiculous pronouncement, including repetition of "51st state", is time spent not doing something useful. I saw some talking head on TV going on and on about it as if it actually mattered. Even asking someone to describe how they felt about their missing cat would be preferable. The greatest threat to our sovereignty is our own insecurity about our sovereignty. A confident people would have shrugged this bullshit off long ago. Whenever some politician starts ranting about "51st" state, someone ought to (figuratively) pull his nose or give him a hard slap on the cheek.