It's an interesting question. Sovereignty is the legal, technical, constitutional issue of who owns what land, and we have a sovereignty issue about where the continental shelf is. You've heard all the UNCLOS debates and that kind of stuff. That's a question of where it is, of where the line is that shows we have official sovereignty over it.
You can have sovereignty over a piece of territory in a technical international sense and not be able to defend it. I invite you to visit any one of a dozen countries in Africa that have technical sovereignty. The boundaries are all still as fixed as they were when they were artificially drawn years ago, but that doesn't mean the country defends them.
That's the line I would draw. I think we need to put a lot more attention on what we have the capability to actually oversee. My definition of defence is a very broad one. I think we have a defence against ecological change and ecological disaster and a defence against not just the militarization and whether somebody's going to attack Ellesmere Island--highly unlikely and almost certainly not going to happen--but whether in fact we have the defence against all the other threats that might come in, things that we don't quite understand.
That's the line I would draw.