Some have proposed that the Turks and Caicos in the Caribbean should become part of Canada.
[T]he prospect of political union has been discussed in both places for quite some time -- ever since 1917, in fact, when then Canadian Prime Minister Sir Robert Borden unsuccessfully floated the idea with London. And it'll be on the docket at this weekend's convention of the New Democratic Party, which has the third-most seats in the Canadian Parliament...Some pros and cons are discussed at the Washington Post.
There is a kind of logic to the argument. Over the course of its history, Canada subsumed various other British territories under its dominion. Unlike the United States' own battle for independence, Canada's political separation from Britain was an evolution by mutual consent. If certain British-run islands in the Pacific can fall under the jurisdiction of New Zealand or Australia, surely the same could in principle be true for Canada with territories in the Atlantic.