And, if we look at integration of Canadian Provinces into the US as various territories and states, and whether that could be a successful project, I would argue that it'd be... marginally successful west of Ontario, and horribly unsuccessful Ontario and east of there (exception: Newfoundland, possibly). The US didn't really have a plan than potential annexation, but that could be along similar lines as the Philippines, with them establishing a republic in their stead.
That is a pretty good start.
I'll have a go at fleshing it out a bit more.
Initially there would be a split into territories based on the different invading forces (Vancouver, Winnipeg, Northern Ontario, Toronto, Quebec, Nova Scotia).
Whatever the final outcome, the objective would firmly control the largest ports and destroy any ability for a hostile power to arise in the former Canada.
The Americans may set up an independent Quebec, but would ensure American military control along the St Lawrence River. They may even take it a step further and set up an Acadian territory from the francophone parts of New Brunswick.
The anglophone parts of New Brunswick are joined to Nova Scotia as is PEI. Newfoundland would also be a separate territory. The Atlantic territories would also be subject to significant military focus. There will be a lot of pressure to make these territories US States.
Ontario would be carved up to weaken it as much as possible. Southern Ontario would be left as a rump territory, albeit the most populous . Far Northern Ontario would be ceded to a US Northern Territory which could encompass the NWT and the far northern parts of the Prairie provinces. Rainy River and Thunder Bay districts could be ceded to Minnesota, Sault Ste. Marie and Sudbury could be ceded to Michigan. The carving up of Northern Ontario is designed to weaken its connection to the western provinces.
The Prairie provinces would become territories and have a more smoother ride to become states in the future.
Vancouver would be hived off to become its own territory and like Atlantic Canada there would be significant military focus on the access to the pacific and a concerted effort to make it a US State. The remainder of BC and Yukon would be added to Alaska territory.
Ideally this contains any ongoing civil resistance to Southern Ontario. However with such a concentrated urban population, civil resistance, both peaceful and violent, would be ongoing. More worryingly for the US it would also be adjacent to some of the most populated centres of mid 20th C United States.
Another flashpoint is how anglophones are treated in Quebec. If they are subject to repression a heavy handed state, Montreal could also be a flash point and a rallying call for the Canadian resistance.