What would North America look like with a smaller USA?

[Alternate History Geek]

What would North America look like in the following scenarios?

Scenario 1: The United States has all of the land comprising OTL's Lower 48 states, but nothing besides that.

Scenario 2: The United States has Louisiana, Texas, and the southern Oregon Country, but not the Mexican Cession.

Scenario 3a: The United States has Louisiana and the southern Oregon Country, but not Texas.

Scenario 3b: The United States has Louisiana and Texas, but not the Oregon Country.

Scenario 4: The United States has Louisiana, but not Texas or the Oregon Country.

Scenario 5: The United States is confined east of the Mississippi.

Scenario 6: The United States is confined east of the Mississippi-Ohio line.

Scenario 7: The United States is confined east of the Proclamation Line of 1763.

Scenario 8: The United States is confined east of the Proclamation Line and north of the Mason-Dixon Line.

Scenario 9: There is no United States per se, but the various East Coast colonies are independent...

Scenario 9a: ...with their territorial claims all the way to the Mississippi.

Scenario 9b: ...with their territorial claims to the Mississippi-Ohio line.

Scenario 9c: ...with their territorial claims to the Proclamation Line.

Scenario 10: Each of the colonies north of the Mason-Dixon Line is independent, but extends only to the Proclamation Line.

 

[Will Kürlich Kerl]

Scenario 1: Basically OTL until around the late 1880s.

Either the Spanish-American war never happens or Spain gets a Hohenzollern King and an alliance with Germany. That means most of the islands in the Caribbean stay Spanish, or become colonies of another country.

Denmark has to sell the Danish West Indies to another country, so it might be Great Britain, or Germany after the 2nd Schleswig War.

No Spanish-American war means the Philippines fall to a different country.

Now, for Hawaii and Alaska, we can have Great Britain get there before the USA, Hawaii eventually becoming a Dominion of Hawaii and Alaska becoming part of British North America/Canada.

Panama leased a strip of land surrounding the Panama Canal to the USA for 99 years. For the USA not to gain that, have the Chilean navy actually attack the US navy in the Panamanian war for independence. That means that Panama stays Colombian.

And finally, for those other minor islands in the Pacific, have the USA stay isolationist and have other powers get them.

 

[Tripwire]

#5 and #6: Everything hinges on Mexico. Demographically, in 1800 Mexico has a population about the same size or just slightly larger than the US's. Perhaps if everything goes well south of the border, Mexico can continue to expand relentlessly northward...In addition to a "much more stable Mexico" ATL, an excellent way to increase Mexican settlement northward would be to have the Comanche collapse due to infighting. OTL their attacks devastated and deeply depopulated Northern Mexico prior to the Mexican-American war, which is something I'm not sure many people are aware of.

If it helps:

Mexican Population, 1803: 5.7 million
US Population, 1800: 5.3 million
Canadian Population, 1806: 391,899
Native American Population, (in present-day continental US borders) 1800: ~600,000*

For #7+, if you mean the 1763 Proclamation Line, there would only be a period of 5 years for a possible POD, since the line was extended to include Kentucky and West Virginia in 1768, and parts further west in 1772, and both of these were followed by immediate settlement.

*According to Russel Thornton, Population History of North America.