At the end of a briefly euphoric week, reality caught up.

On one level, Friday’s news was not really surprising. The French rating downgrade was a shock foretold. As was the breakdown in talks between private investors and the Greek government about a voluntary participation in a debt writedown. A proposition that was unrealistic to start with has been rejected. We should not feign surprise.

And yet both events are important because they show us the mechanism behind this year’s likely unfolding of events. The eurozone has fallen into a spiral of downgrades, falling economic output, rising debt and further downgrades. A recession has just started. Greece is now likely to default on most of its debts and may even have to leave the eurozone. When that happens, the spotlight will fall immediately on Portugal, and the next contagious round of downgrades will begin.