By Stephen Mulvey
BBC News website
This would not be an easy time for any country to take over the presidency of the European Union.
Tony Blair wants to focus the EU on jobs, growth and competitiveness
The crisis over the constitution has left the EU drifting without an anchor, and the rows over the budget have caused deep divisions.
But the job is particularly awkward for the UK, because of its combative stance on the budget, and its conviction - not universally shared - that the constitution impasse obliges the EU to radically re-think where it is going.
Both these big issues could easily be left for the Austrian and Finnish presidencies to grapple with in 2006.
But instead the UK seems determined to put on a display worthy of the memory of Waterloo and Trafalgar, or even the heroic but pointless Charge of the Light Brigade.
It is going all out for a budget agreement, and it insists that the constitution crisis is actually an "opportunity" to persuade European partners of the need for liberalising economic reforms.
The UK's stint at the helm of the Council of the European Union will be judged partly in terms of the scale of the debate it has provoked on this agenda of jobs, growth and competitiveness and the number of hearts and minds it has won over.
Tony Blair made an impressive start with his speech in the European parliament on 23 June, but there are many pitfalls and obstacles to negotiate, including the risk of sounding preachy or unsympathetic to European social traditions.
"He will have a tricky time doing this without appearing hubristic about the successes of the British economy," says Hugo Brady of the Centre for European Reform.
SOME AGENDA HIGHLIGHTS
Attempt to reach budget deal
Start Turkish accession talks
Reform of sugar subsidies
New push for services liberalisation
Improved EU law making - more consultation and better impact assessment
Agreement on mutual recognition of evidence (European evidence warrant)
Progress with REACH chemicals legislation
Increased aid to Africa
"In continental Europe, you have to remember, the UK is seen as a bastion of American-style capitalism."
This is to say nothing about the difficulty of winning over European leaders who are already angry with the British, such as Luxembourg's Prime Minister, Jean-Claude Juncker, and French President Jacques Chirac.
A former European adviser to the prime minister, Sir Stephen Wall, sees this as a definite hindrance to any deal on the budget.
"Will Chirac want to be the guy who hands Tony Blair a great success on a plate? Pretty unlikely," he says.
A head-on clash with France is also likely on the Services Directive, which aims to open up the EU's market in services to real competition.
The UK describes it as "an opportunity to make one of the biggest improvements to the Single Market since its original creation, potentially creating hundreds of thousands of jobs and billions of euros for the EU economy."
In France and Germany, by contrast, the directive has been described as a recipe for "social dumping" - helping new EU countries with low labour costs to undercut richer competitors.
"We could have real problems with the French here," says one UK official, "and possibly other countries as well."
It might be tempting for the British to dilute the directive, or put it on the back burner, but once again they seem to be adopting bulldog tactics.
"If Tony Blair wants to have a debate on economic reform, he cannot do it by pushing the Services Directive under the carpet," says Mr Brady.
Another challenge the UK faces is shortage of time. Its six months gets whittled down to four-and-a-half months, once summer and Christmas holidays are taken into account.
The window of opportunity for taking big decisions only begins in October, after the German general election due in mid-September.
It makes a difference to the UK who wins the German election
The good news for the UK is that the new German government may be more enthusiastic about economic liberalisation - the bad news is that it may be opposed to the start of membership talks with Turkey on 3 October.
This is a top priority of the UK presidency, but one that may not be easy to deliver.
Enthusiasm for further EU enlargement, and especially for Turkish membership, has waned sharply in some countries since the French and Dutch votes on the constitution - even the European Commission had a "lively debate" on the matter before issuing its proposed framework for the negotiations on 29 June.
In this final part of the year, when the main Council decisions are likely to be taken, the international agenda also becomes hectic.
There are EU summits with Russia and Ukraine in October, and a summit with Canada at the end of November, followed by a major UN conference on climate change.
The World Trade Organization ministerial meeting in Hong Kong in December actually overlaps with the final European Council of the UK presidency.
Britain's European diplomats are renowned for their skill, which is lucky, because there is a lot on, as well as some difficult briefs to handle.
However, one advantage of a big and varied agenda - ranging from climate change and chemicals legislation to counter-terrorism, trade and aid to Africa - is that there ought to be some hits as well as misses.
Europeans wondering what the EU exists for, after the chaos of the last few months, should get at least some answers.