You’re right Bob that the closest point between Africa and North American would be somewhere in eastern Newfoundland, perhaps Cape Race?

And Mercator is a terrible projection to show size. (Greenland is larger than South America, when in reality, it’s about 1/6 its size.) But it is pretty good at shapes.

I think antipode is what you are looking for — the exact point opposite another on the earth. If you search for antipode maps you’ll see a lot. Here’s one (and, from the US you WON’T end up in China!) https://www.geodatos.net/en/antipodes