edge--effects asked:

Is there any way Amtrak and ViaRail could conspire to connect across the Detroit River? It would definitely be really complicated legally and structurally, but when I’m going to visit my brother in Toronto and take the train instead of driving, it would be beautiful to not have to get a ride across the border to the ViaRail station in Windsor

Oh very easily, we just need the funding to build it and congressional or state approval. Other joint US-Canada services exist like Cascades and Maple Leaf