Why didn’t Americans continue territorial expansion claiming the entire South American countries below?

Probably because those countries had already been under the rule of Spain and Portugal since the 16th century and attempting to conquer settled lands with a long history of colonialism by another country where they don’t even speak the same language was not worth the effort. Americans did gain lands from Mexico, though.

All of that plus I suspect they felt it would be too hard to govern such an expanse effectively.

Most of the border region of Northern Mexico is desert or close to it. Why would anyone want to push into that?

The US did try to take Canada a couple times, but it was a little too much for the US Army, eh.

I was thinking the same thing…why not Canada too? Not enough population?

They weren’t given the latitude.

^^^^Ha!