Well, it seems to me that, from the legal angle at least,
zomg’s expert friend is right on the button.
Without unanimously-approved changes to the EU treaties, whatever accord the other members come to can’t be implemented by the existing EU institutions – or at least not enforceably – for example, if there is any dispute as to penalties for breach of whatever the fiscal requirements are the ECJ will have no jurisdiction to deal with it. And without that, it pretty well comes down to Germany bossing the rest of the EU, which isn’t exactly the political outcome that anyone (even Germany) wants. In the short term (as in immediate and now), sure, France will blame the UK. But medium-term France may well be the first to default and want protection given their banking exposures.
Now I’m not saying that the UK government’s approach would have been right in all possible circumstances. If, for example the political will were more aligned across Europe then it might have been a bad move. But as things stand this is a rational stance for the UK to take, it hugely improves our negotiating position, allows the Eurozone to push for internal reforms without affecting other countries, but also allows a backstop renegotiation of the EU treaties if it doesn’t work. I don’t believe for a minute that the other governments didn’t see this coming, and they know well enough that it provides a second line of defence. So for all the posturing that is going on it is a good move for the UK
and for the Eurozone.
Notice that I’m not personalising this to Cameron or to the Tories. It would have been a good move whichever party was in power here.