Why Isn’t Canada Part of the United States?

How some British colonies in North America stayed out of the Revolution

Hypothetical American flag with sixty stars, for the addition of Canada’s ten provinces.

An international border runs across North America, from Passamaquoddy Bay on the east coast to Point Roberts on the west. Millions of people cross it, yet few ask why it exists in the first place.

Any student of American history knows the country was formed from the thirteen British colonies which rebelled against the Crown in 1775 — New Hampshire, Massachusetts, Rhode Island, Connecticut, New York, New Jersey, Pennsylvania, Delaware, Maryland, Virginia, North Carolina, South Carolina, and Georgia. But these were not the only British colonies in North America at the time. There was also Florida, recently acquired from Spain, the Colony of Nova Scotia (including present-day New Brunswick), the Colony of Prince Edward Island (called St John’s Island at the time), the Colony of Quebec (including what is now southern Ontario), Prince Rupert Land around Hudson Bay, and if we jump across the Gulf of Saint Lawrence, the Colony of Newfoundland. Florida ended up being incorporated into the United States, but the others didn’t. Why not?

Of these colonies, Nova Scotia and Quebec were by far the most populous and important. And at first glance, it’s not clear why they didn’t join in the rebellion. The British…