With a POD in 1870, what is the most plausible way for the the USA to rule the entire Western Hemisphere by 2010.
Here are the rules:
-the USA must remain a free and democratic nation the entire time
-American culture must remain, for lack of a better word, American.IE, majority English speaking, capitalist, with a slight center-right social leanings.
-No genocides or Apartied. As far as Nukes go, limit is 5.
How can it be done?