If the rest of the EU adopts the constitutional treaty but the British vote against it, the Union faces crisis and instability. Charles Grant looks at what may happen next. Would there be a second referendum, or an attempt to renegotiate the treaties? Would the other countries try to push ahead with the constitutional treaty, excluding Britain from the EU? Or would France and Germany try to establish a 'core Europe?' Grant concludes that the most likely outcome would be a 'messy core', with Britain outside the leading group of EU countries. He argues that this would be bad for Britain, bad for Europe and bad for the US.

Charles Grant is the director of the Centre for European Reform.

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