As for the relevance of the Nuke free debate; I agree it's not likely to change now. It's not even very important whether it does. That was a policy based on a war that's over now. In the next war, other policies are going to be more important.
However, I think the ideas and attitudes behind the decision ARE still relevant. As you say, it seems to be echoing back in this debate over GE foods. If the attitudes and assumptions are wrong, they will continue to poison the debate over everything for decades to come. If they are right, then the way the apply to modern problems needs to be established.
Some people might see it as just rehashing old cold-war arguments. I see it as a continuing search for truth.
Hoping to find out more about the ANZUS breakdown, I came across this, which contains both the original treaty, and the anti-nuclear act. The ANZUS treaty constantly mentions Asian threats (including Japan), and the pacific region, and also goes on to say that parties will 'meet the common danger in accordance with [their] constitutional processes'. It doesn't specifically mention any right to ship visits, and it cannot be seen to speak the language of global nuclear war - it's just too old to do that. What it does say that favours the American decision, is that parties will 'maintain...collective capacity to resist armed attack'. However, it doesnt mention suspension of members - just that there is a requirement to give a years notice if a member wants to leave the treaty.
It seems to read as a document designed for wars in the Asian/pacific area in the wake of the second world war, and wars such as Vietnam, which me met our obligations over - despite large protests from the now standard rabble of all too idiotic and idealistic peace-obsessed halfwits (haha). The kind of people you seemed to be thinking of in an earlier post.
ANZUS wasn't designed for the kind of 'war' the US was involved in with Russia - and I think our suspension from it was more to do with making an example of someones anti-nuclear policy - after all, there were countries, and as you say, even cities, that were getting a little sick of the nuclear aspects of the cold war. It seems quite possible that it could have been reinstated any time since ?1994(?) when US warships stopped carrying nuclear weapons.
Ive had a brief read of the paper at the site above, and it seems to go as far as to say that the suspension decision was based partly over ignorance of New Zealand the kind weve seen so much on this thread with all those silly communist claims. The paper also mentions that over 70% of the US fleet uses non-nuclear propulsion which rules out capital ships and submarines. Maybe there was good reason for the stranger part of the anti-nuclear act. Seems it's about time the suspension ended anyway.