The reason we bought non-nuclear subs is two-fold.
First and foremost - Canada has a non-nuclear defense policy. Which is why we have nuclear plants, but no nuclear missiles. We just choose not to fight our battles with radioactive materials.
Second, nuclear subs are actually noisier than diesel/electric. When "going electric", a DE sub is much quieter. The main advantage of a nuclear sub is that it doesn't have to stop into a friendly port to refuel, so it can go long long distances without pulling into a friendly harbor. Since Canada is using the subs to protect fishing rights (scare off the Japanese, Portugese, Spanish, and French fishing trawlers) and to patrol the Northwest Passage (under pressure from the US to do this), the subs will always be within range of a friendly port.
Thus, no need or desire for a nuclear sub. In many ways, should the sub ever see battle, it's better that it's diesel/electric from a stealth/tactical perspective. Also, these subs are recent, good fighting machines, not some old outdated undesired piece of crap (at least on paper!). Britain got rid of them (on paper) because they elected to go with an all-nuclear fleet.
Not so sure how they could have gotten all banged up like that, but it will be interesting to follow the scandal as we figure out who really screwed up. My sympathies go out to the families of the poor sailor who died.
edited: for clarity
Edited, Fri Oct 8 09:12:49 2004 by fmagnet