This weekend’s deal in Brussels is the shape of the European Union’s future. It is messy, contradictory and very likely open to legal challenge on its important points of ambiguity. It is also a good representation of what the 27 members of the European Union have in common — which is less than the rhetoric suggests, and is getting smaller.

The treaty is a success for Angela Merkel, if that success is deemed to be the existence of a piece of paper that was not there before. But the text was secured after an ugly scuffle, which left it crinkled, torn and taped together.

It is not a triumph for Tony Blair. When he scheduled his final appearance on the world stage, he could have foreseen that the EU summit would have the bad temper of a production where the stars rewrite their lines up to the last minute. The “red lines” that he defended are scuffed and blurred; it remains to be seen exactly what Britain has secured, and that may emerge only after expensive and unpredictable court cases. The battle left him isolated, forced to assert Britain’s deep differences from the Continent; precisely the position he wanted to use his premiership to leave behind.

It does not bode well for his role as some form of Middle East envoy, in the unlikely event that his team and the US manage to staple that together — never mind by Tuesday, the last day of his tenure, as they have wistfully hoped.

A bluffer's guide to the EU treaty

Our correspondent hacks through the verbiage to explain what happened at the EU summit and what it means

• Patchwork deal proves Europe cannot heal its deepest wounds

BACKGROUND

• Unconstitutional

• Fresh start or revived constitution?

• Merkel’s dream; Britain’s nightmare

• Brown’s first test: how to avoid an EU constitution

• Europe divided over summit plans

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• A bluffer's guide to the EU treaty

But he was not helped, in pursuing his last dreams of putting Britain at the heart of Europe, by having to act as Gordon Brown’s foreign secretary. The enduring image of the weekend is of the growling phone calls from the prime minister-designate, who mustered the self-restraint to stay in London but who erupted with incredulity at what Blair was about to sacrifice for the sake of a deal.

When Nicolas Sarkozy, the new French President, said that “I am sorry that Mr Blair is going — he has always been a man who sought compromise in Europe”, he was paying the kind of compliment that no British prime minister would want to accept, but was surely speaking from the heart. The expectation, after this weekend, must be that Brown will be as vigorously “Anglo-Saxon” as France has feared.

The messiness of the deal, with its patchwork of opt-outs, opt-ins and seven-year delays, shows the narrowness of the agreement between the 27 members. That should not be a surprise. But the result of so brutal a compromise is that important points remain ambiguous.

Britain believes that it has secured a watertight exemption from the Charter of Fundamental Rights, but that may not be so clear-cut that it discourages legal challenge. The powers of the new “high representative for foreign affairs and security policy” are as unclear as the job title; whether this person can determine European policy will emerge only in practice.

Most important — the point Brown rightly seized on — is that the text has glossed over the clashing visions of the union held by France and Britain. France’s success in deleting the pursuit of competitive markets from the EU’s goals may override Britain’s countermove of inserting a clause asserting its importance. The fudge is an invitation to legal disputes, and shows that the EU may clash even more passionately on points of substance — such as subsidies to state companies — than it has managed this weekend on procedure.

Finally, the bitter row between Germany and Poland is the symptom of a profound problem. Jaroslaw Kaczynski, the Polish Prime Minister, was extravagantly provocative in invoking Polish deaths in the Second World War as a reason for it to have a greater voting weight. But so was Angela Merkel in threatening that Poland may lose cash in the next budget round and then, at the brink of the negotiations, that she could simply leave it out of the treaty.

The depth of Poland’s sense of victimhood has not yet been plumbed in EU summits but, all the same, some of it is justified. The dispute represents the EU’s continuing difficulty in accepting its new, poorer members on equal terms, while taking for granted their role as a bulwark against Russia.

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