Trudeau mentioned it is just for people, trading and "deliveries" continue as usual.

Tourism, certainly, but that's already in the toilet regardless of who our border is open to. Even for overseas countries, we imposed no restrictions on trade or commerce, only visitors. I doubt this accounts for a non-trivial fraction of our economy, especially with public spaces already shutting down.

I don't even understand how you can generate this comment. Have you been watching developments around the world at all? China completely shut down, followed by so many countries I can't even keep up at this point. I'm living in a country (not China) where the mega metropolis capital city has been forcefully quarantined. How do you look at all this and think "the economy!" The world is way past that point. This is bigger than the economy, or maybe you know something that the rest of the world doesn't.

In other words, the world economy is beyond screwed. That's already in the rear view mirror. We're going all in on stopping the spread.

You can bar people but still allow trade. The economy is going to grind to a halt regardless.

That is a good consideration, but I think the US also has demonstrated some terrible handling of the situation - it's not super clear just how dire the situation in the US is because they have such a poor handle on tracking disease progress.

Yeah from my understanding the automobile industry parts pipeline knows no borders. Closing the border could essentially mean shutting down all the car factories.

If the Detroit/Windsor border crossing was closed, you can take another 15-25% off the NYSE.