The remarkable thing about the European Union is how far this project has come without its partners ever deciding what it was for -- or, more precisely, where it would stop. The crisis now facing the EU demands answers to those questions. But this is not the first time that circumstances have demanded such answers. The European way is not to provide them, which would be hard, but to keep on muddling through.

It has always worked before. As I say, the Union has come this far, and it has been a stunning achievement. Governments will doubtless try the same approach once more. This time, though, I wonder if they will finally hit the wall.

For reasons I explain in this column for National Journal, I think they will.