Actually, I love the fact that there's a debate. In fact, I maintain that Canada is not asking for an exception to be made for the Northwest Passage, to exempt it from the straits regime. I believe the Northwest Passage does not fulfill the criteria for an international strait under international law. You're right that the convention does a very poor job of giving us a definition, but if you dig into the conference itself and go into the case law, like the Corfu Channel case, it's established. There's a geographic criterion and of course a functional use criterion.
Although there's a slight debate about whether it is actual use or potential use—and that plays in the case of the Northwest Passage—for many of these key straits you're mentioning, it's well established. Even countries aren't debating it. It's well established at this point.