What If....Scenario After Polk Presidency

 I'm a map guy....I could spend hours each day looking at historical map.

This map?  It's what existed during the Presidency of Polk (1845-1949).

So you gaze at it....Mexico line? It goes 200 to 300 miles south of today's line.  

Yucatan?  Part of the US.

Cuba?  Part of the US.

Had things stayed the same?  You'd have five to six additional states today.