Automobiles are a great example! Yes, those parts cross the border multiple times and that's exactly why they are excluded from counter tarrifs!

You can check for yourself:

https://www.canada.ca/en/department-finance/news/2025/03/list-of-products-from-the-united-states-subject-to-25-per-cent-tariffs-effective-march-4-2025.html

It is also why trump just exempted automobile parts, his tarrifs hit them, ours basically didn't. (I think we have tires because we finish those as a whole part and the production chain is a bit different for those.) The overwhelming majority of the effect on American auto stocks is because of self imposed costs to American businesses.

We're not aiming our tarrifs at things that will target our own factories. Look through the list and let me know what you think looks like a production input that would get refined here and then sent back.

Edit: For more evidence, you might look at today's stock rally after trump announced delaying auto tarrifs. You'll note Canada made no mention of lifting any of our counter-tarrifs and it'd be weird to assume there'd be a massive change in boycotts or diversification off a one month tarrifs reprieve in one sector.