The prospect of a No vote in the Irish referendum next month on the European Union’s Lisbon treaty is something too dreadful to contemplate in Brussels and most of the capitals of other EU member states.

“There is no Plan B,” says José Manuel Barroso, president of the European Commission. “Let us hope the Lisbon treaty is ratified. If it is not done, we will all pay a price.” After the exhausting negotiations that came after rejection of the EU constitutional treaty in France and the Netherlands in 2005, no one wants to think about the consequences of another rejection.