I am not going to debate this .....here watch this ..Sam Sullivan has a great website with lots of Video Blogs about local history.
http://youtu.be/jVBaut5YjyA
That video depicts EXACTLY what I'm talking about. The Americans wanted the entirety of "Columbia" south of the 49th. The video is very light on details, but it depicts how the area of southern Vancouver was contested.
Anyways, moving right along, I guess...