It's not added to the treaty, because of course NATO's nuclear posture is not part of the treaty. It's a policy. It's updated, reviewed, and changes are made quite regularly. There's a long history of footnotes to various aspects of the policy. It's not necessarily just the nuclear policy but when countries have disagreements about particular elements. It just reinforces the point that this is a policy and not a treaty obligation, and therefore this step can be taken, although there would of course have to be agreement of....
The real point of the footnote is that individual countries can absent themselves from particular aspects of the policy. The most famous aspect of that is France staying outside of the nuclear planning group. So although it works by consensus, when it's making positive statements, there is this very interesting mechanism to allow for differences of view on specific aspects of the policy. That gives Canada and others who want to push, who want to get a dialogue going, room to manoeuvre. It's not an “all or nothing”. You just don't say the policy has to change tomorrow. You can say, no, we disagree with this, we're taking this step now. Hopefully, this will engage a dialogue with others as to further steps we can take.