The Irish Presidency of the European Union, just beginning, is probably not only the last Irish Presidency there will be, but also potentially the most important.
If the Irish Presidency can get agreement on a new EU Constitutional Treaty, this could make it our most successful presidency yet. On the contrary, if the Irish Presidency satisfies itself with marking time on the constitution and gives in to those who want to put off hard decisions, we could find ourselves with one of our least successful presidencies.
There are forces within the European Union who will be quite happy to continue on with the Nice Treaty and who do not want the efforts required to agree a new constitution. France, although a vocal ally of Germany in its recent argument with Spain and Poland about vote reweighting, might actually prefer to stick with Nice which gives France much more voting weight than the proposed new system.
Britain also sought to fish in troubled waters in the lead-up to the recent Brussels summit, giving encouragement to Poland and Spain and thereby complicating the Italian presidency's effort to find a deal.
After the summit collapsed, the Taoiseach, Mr Ahern, was right, in tactical terms, to play down the prospect of an agreement during the Irish Presidency. A lowering of expectations is no harm, so long as it is only a tactic. But the reality is that both Ireland and the rest of the EU have a great deal to lose if we fail to get a quick agreement on the European constitutional treaty.
First of all, failure to get a quick agreement would mean that the disputed issues in the constitutional negotiation would become part of the platforms of the various national parties contesting the June European elections. This electoral contest would harden the position of various governments and making it more, rather than less, difficult for the issues to be settled afterwards.
Parliamentary elections, contested against the background of the uncertainty about the constitutional arrangements under which the parliament will operate, are likely to throw up more MEPs who are Euro-sceptic and this will make the task of getting a sensible policy through the next European Parliament more difficult.
But an agreement on a new constitution, under the Irish Presidency in March, would ensure that the European elections would take place in a constructive and forward-looking atmosphere and this would be good for European democracy.
Secondly, there is a real risk that if agreement on the constitution is delayed, constitutional questions will become entangled in rows about money.
In July 2004, intensive negotiations will begin on the terms of EU spending for the period 2006-2013. If the constitution has not been agreed before that financial negotiation starts, some countries will seek to get money in return for support for constitutional improvements.
That sort of horse-trading would not only give Europe a bad name, it would also give Europe a bad constitution!
One of the countries which was particularly difficult at the summit in Brussels was Spain. Along with Poland, Spain held out for the old Nice formula for counting its vote in the Council of Ministers which gave it almost twice as many votes per head of population as Germany.
Spain will get a new Prime Minister in March, as Mr José María Aznar has announced his retirement. Mr Ahern would find it much easier to get an agreement on tricky constitutional questions from an outgoing Prime Minister than he would if he has to negotiate after March with a new Spanish Prime Minister, who will be only beginning to find his feet in his new job.
Finally, even though there was no agreement in Brussels last month, some momentum was built up. Certain agreements were written in in pencil, but time did not allow them to be overwritten in indelible ink.
The more time passes, the more will the pencilled agreements fade. Eventually they will be erased completely and participants will say they never made them or that they were made by predecessors and are no longer binding. This argues for a rapid attempt by Mr Ahern to nail down these tentative agreements secured by the Italian presidency, and to close all other disputed issues early in the Irish Presidency.
How should he do this ?
As the Taoiseach who led the last Irish Presidency, in 1996, I have very clear advice to offer the Taoiseach. There is no substitute for one- to-one, face-to-face discussion between the President in office and the heads of government of each of the other 24 countries.
The Dublin summit of December 1996 would not have been a success if I had not undertaken a tour of all of the 14 other capitals in the weeks leading up to the summit itself.
That tour gave me an insight into the worries of each of the participants in the negotiations. It established a personal rapport. After all, there are few better ways of getting to know someone than visiting them in their own home or at least in their own home country.
In the present case, the Taoiseach has the bigger task of visiting 24 capitals, but the issues to be settled in the constitutional negotiations are now narrowed down. It should be possible for Mr Ahern, especially if he arranges to visit the capitals in the right order, to build up a momentum towards agreement that could make it possible for him to conclude the entire deal at the summit in March.
He should leave the most difficult capitals, the ones with the trickiest outstanding demands, to the end of his tour, so that he can present them with the consensus viewpoint of the others. The Minister for Foreign Affairs, Mr Cowen, could perhaps tour capitals in a reverse order so that he can brief the Taoiseach for the last few vital meetings.
In an article published in The Irish Times before Christmas, the Taoiseach admitted that there is now a perception among many EU partners that Ireland is among the less-enthusiastic participants in the European project. There would be no better way to restore our pride in our European Union membership than for an Irish Presidency to be the one that gives Europe its first constitution.
Let us suppose the Taoiseach decides he is not going to take the risk involved in going all out for an agreement at the March summit. What else could he achieve during the Irish Presidency? Not much of substance, I submit.
Of course, we will have another instalment of the so-called "Lisbon process" at the March summit, wherein the progress of EU member-states in making their economies more flexible, investing in research and development and combating social exclusion is to be benchmarked.
This is a "motherhood and apple pie" process. There are no sanctions for bad performance and no incentives for good performance. The only pressure is peer pressure and at the end of the day, the peers in question are not much interested in what others are doing anyway.
The Irish Presidency will, of course, organise planned summits between the European Union and other parts of the world like the US and Latin America. These summits are probably essential for maintaining a long-term structure of good international relations. But the likelihood of any short-term advances is minimal.
I mean no disrespect to the Taoiseach in what I am about to say, because he is a clever man and a successful politician, but just as Bill Clinton told his campaign workers in 1992, "it's the economy, stupid", I would say to Mr Ahern in regard to the Irish Presidency of the EU, "it's the constitution, stupid".
Mr Ahern and Mr Cowen have the capacity to deliver agreement on an EU constitution, where the Italians failed. To borrow an old Fine Gael election slogan, all they need is the courage to succeed!
John Bruton TD is a former taoiseach and president of the European Council.