December 9, 2011: A ten hour summit meeting in Brussels that lasted until the early morning hours will bring changes to the eurozone – and possibly even to the European Union's composition. This year's eurozone sovereign debt crisis involving its weaker members prompted France and Germany to seek changes to the eurozone's rules and mechanisms. German chancellor Angela Merkel wanted the changes to be enshrined as an amendment to the EU Lisbon treaty, the EU's current de facto constitution.

However, Britain's prime minister David Cameron refused to go along with any amendment to the Lisbon treaty that might eventually threaten his country's financial independence. Cameron's refusal took place 20 years to the day after European leaders agreed at the EU Maastricht summit to create the single currency, with Britain opting to stay out at that time.

Cameron's decision left his country isolated, as the other 26 EU members – 17 eurozone members and the remaining 9 other EU members – agreed on drafting and implementing a treaty for a fiscal union that would tighten eurozone rules and require automatic penalties for violations, providing greater EU oversight over the domestic fiscal matters of eurozone members.

France gave up its opposition to automatic penalties, which Germany has pushed for since the beginning of the current eurozone debt crisis. The new treaty is to be drafted in the next three months and would need to be ratified by all eurozone members. "The 17 members of the euro group have to win back their credibility. I believe that can and will happen with today's decisions. This is a breakthrough to a union of stability. We will use the crisis as a chance for a new beginning," Merkel said at the conclusion of the summit.

Even though Britain's refusal to participate will mean that the Lisbon treaty will not be amended, that treaty allows individual EU members to reach agreements among themselves without requiring all EU members to participate. Earlier examples of such agreements are the Schengen treaty on freedom of movement across national borders of Schengen members and the eurozone itself. Today's agreement in Brussels to create a fiscal union among 26 of the 27 EU members would be another example.

In fact, the summit result again prompted political leaders and analysts to refer to a "two speed Europe" comprised of those EU members desiring closer integration and those EU members – currently only Britain as far as the proposed fiscal union is concerned – who desire the benefits of the free trade zone without committing to closer political and economic ties.

In an interview with Germany's "Bild" newspaper, Martin Schulz, a member of the European Parliament for the Social Democratic Party of Germany, wondered whether Britain would remain a member of the EU. "I doubt whether Britain will remain a member of the EU in the longer term. The EU would survive without Britain, but Britain would have difficulties if it left the EU."