In terms of missile defence, the defensive systems are oriented really towards one very specific threat, which is what we would have called a rogue state, with a limited number of missiles and weapons. In the current climate, that's a North Korea and potentially an Iran in the future, and possibly other countries.
The Russians have agreed to build a nuclear reactor in Egypt for some reason, so one has to wonder what the story will be there in the longer run. Other gulf states have been seeking nuclear energy capability for no particular reason as well.
What needs to be borne in mind with regard to missile defence is that we need this debate, and that's really the purpose of my comment. It's highly unlikely the U.S. would seek to put any kind of interceptor on Canadian territory—and probably no radar, or just one—so we're talking about a very limited request on the part of the U.S.