Somehow, make United States 'manifested her destiny' to the north toward Newfoundland and to the south toward Caribbean Sea, instead of to the west toward Pacific Ocean like in OTL. By 1860 US have acquired control of Quebec, Newfoundland, Labrador, and most of Caribbean Islands. (but never acquired Lousiana, Texas, and other territories west of Mississippi River)
Is this too implausible? What is the most plausible way to do this? What would be the consequences to the ARW? And the rest of American history?
Is this too implausible? What is the most plausible way to do this? What would be the consequences to the ARW? And the rest of American history?