Canada

I'm going to play devil's advocate here. Our economy is, unfortunately, still reliant on trade with the US and this won't change anytime soon. Carney's goal to double non-US exports over the next decade (which is considered hard FYI) will still keep the US as our largest trading partner. This specific ad has had massive visibility in the US (ironically because Trump drew attention to it) and has largely already accomplished its goal. The threat to our economy, just to play an ad, probably isn't worth it.

That said, we need to track every concession we've ever made to the United States on trade (including these newer items, such as the Digital Service Tax) and make it clear that these concessions are contingent on free trade. If we don't maintain free trade, we're reclaiming these concessions. These should include items from years ago like more restrictive copyright laws, longer patents on pharmaceuticals, etc. We also need a red line as to what concessions we won't grant even if it causes an economic disaster or else Trump will keep demanding more and higher concessions (we may already have such a red line - I expect they wouldn't publish it).

Lastly, we need to view free trade with the US as a temporary thing to keep while we disentangle our economy with theirs. We can't have our entire economy paralyzed by uncertainty all the time, but businesses won't invest elsewhere unless they know that trade with third nations will remain the better option even if US trade temporarily normalizes. That is something we could control, but it would require our government, with Conservative support, to announce that Canada will withdraw from / not renew CUSMA in X years, no matter how the US situation changes. The Conservative support is necessary so that businesses don't believe CUSMA might survive depending on an election outcome.