In Georgia Strait, which is inside Vancouver Island so in no way outside any territorial waters there is an area known as Whiskey Golf that is a military activity area. It is near the Canadian Forces base at Comox.
This area, smack in the middle of the strait and on the Rhumbline of many cruisers' tracks, is often used by primarily Canadian and US forces, but also others as well. Activity warnings are given daily on the weather VHF channels and there is usually 2-3 days/week that transit is forbidden.
It's a bit galling but on the other hand most of the activity involves subs, torpedoes and sub trackers and they are often firing live and unarmed torpedoes. We have often sailed nearby on active days and seen no ships - and have seen boats that apparently didn't listen to the radio transit the zone at that time.. wonder how they'd feel if even an unarmed torpedo "found" them accidently...
On one occasion we were gybing down the eastern edge, fully aware of our position when we were chased down by an unmarked patrol boat, closely examined from a boat length astern by an officer with binoculars that had 6" lenses (must have been gauging how recently I'd shaved) before telling us not to sail above a certain heading for the next 10 miles (which we already knew..) This vessel had no Canadian markings/flags for sure, and none others we could see. btw - this was pre 9/11 so the terrorism factor wasn't prominent yet.
So while it's annoying to be kept out of certain waters, given what they might be up to "down there" it may be prudent to keep your distance..
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)