The Prime Minister's about-turn on an EU referendum hasn't only left his ministers struggling to catch up. Newspapers are also having to work out where they stand on this contentious issue.
Eurosceptic papers are cross that their fox has been shot, depriving them of grounds on which to attack the Prime Minister; pro-European papers are suspicious of being forced to rally once again to the EU standard. Almost all are united in their call that the issue at stake should be the constitution itself.
Most journalists know there is little chance of a debate that is confined to the details of the document. Instead, rows over the poll's timing, over the question being asked, and over campaign funding will replace the issue of whether to hold it at all. Through all this Mr Blair must find room to sell a document giving more power to Brussels.
Alastair Campbell, his former director of communications, liked to claim that the British people could be persuaded to vote for the euro within six months of a recommendation to enter. There is much from those plans that can be dusted down and made to work again.
Most of those who were recruited to the euro cause can be expected to help out, but the game of celebrity endorsement could end in stalemate: while Eddie Izzard may back Mr Blair, Bob Geldof could do the same for the other side. Downing Street, meanwhile, has ordered all departments to produce concrete examples of everyday benefits of the EU to UK citizens.
Michael Howard and his press allies have been disciplined, so far, in insisting that Britain's membership is not in question. But it is inevitable that sooner or later the hardline sceptics will be forced to break cover.
The Daily Express's switch of loyalty promises to draw its right-wing rival the Daily Mail into a fight for editorial distinctiveness. Mr Blair will be hoping that the two titles embark upon a Dutch auction of Euroscepticism. Editor of the Express Peter Hill said it was too early to tell what his paper's position might be on re-negotiating Britain's EU membership. But he added: "The huge majority of the British people don't want the constitution. It is a folly for newspapers to fight their readers as it is political parties to fight their voters."
The News International titles, by contrast, can be expected be very careful to limit their attacks. The Sun may be more brutal than The Times but both will aim their fire at the detail of the constitution rather than at the EU itself.
The attitude of titles in the pro-Europe camp, including that of The Independent, might be described as one of qualified enthusiasm. "We never saw the need for a referendum," said Simon Kelner, the Editor of The Independent. "But we welcome the opportunity to get involved on the pro-euro side of the debate, which hasn't been heard too widely in the press so far."
It is the Financial Times' position that will most worry Downing Street. There is nothing as wounding as reasoned criticism from an erstwhile friend, and the FT's reaction to the referendum announcement was withering.
Mr Campbell's strategy to win the euro referendum relied on a short campaign. But a poll on the EU constitution could be two years away. That's an awful lot of column inches to play for.