How Gordon Brown must wish that John Branche had set the tone for all future Lord Mayors of London. This sturdy member of the Draper’s Company, elected in 1580, declined to hold the annual banquet expected of his office. The Privy Council was outraged and screamed for an explanation. No mayor since has failed to provide a feast. But if Branche had created a precedent then Mr Brown would not tonight be delivering his first Lord Mayor’s Banquet address as the Prime Minister.

It is a fair bet that he will loathe the occasion. If the dress code (white tie) were not bad enough, both the pomp and his fellow guests will be discomforting for him. There will be archbishops here, ambassadors there and aristocrats everywhere. It is the Establishment’s equivalent of a day out for the workers at the seaside. Tony Blair enjoyed it. David Cameron would feel at ease (it is, after all, not unlike a “come as you are” party in the Notting Hill area). This is, in short, no place for a Puritan such as Mr Brown.

What makes it worse is that tradition dictates that his speech be about the international situation. This would not be Mr Brown’s ideal choice of topic. He would much prefer to bang on about alleviating poverty (a shade ironic with that audience), education and training or his blueprint for the NHS. So he will be stuck in a place he would rather not be, with people who he would rather not share a meal with, discussing a subject he would rather avoid. Rarely can a quiet night in with the telly have appeared so attractive.

For although he has been in No 10 for just 140 days, certain defining features of Mr Brown’s approach to foreign policy have already become apparent. These consist of 11 words: less of it, more peace please, and it’s the economy, stupid.

Mr Brown is perfectly willing to do what he must abroad, but he does not ache to be an intercontinental celebrity such as his predecessor. He saw at close quarters how Mr Blair’s (brave and bold) deeds in Kosovo, the aftermath of September 11, 2001, and, most dramatically, the removal of Saddam Hussein distracted him from the domestic agenda, divided the Labour Party and cost support with voters. Mr Brown will prosecute the conflicts that he inherited but he is not looking for any more wars, thank you. In practice, this Prime Minister treats foreign affairs as if they were an extension of the initiatives he took when at the Treasury. His instinct on controversies such as the Israel-Palestine dispute or the plight of Africa is to conclude that economic development is the foundation for enlightenment.

These principles have produced three short-term imperatives for him.

First, to muddle through with the Anglo-American relationship until January 20, 2009, when George W. Bush must leave the White House and someone more congenial replaces him. This US Administration has achieved the rare status of being made up of people with whom the Prime Minister would care to spend an even shorter period of time than those who will attend the Lord Mayor’s Banquet.

Secondly, to press the EU reform treaty through Parliament in a manner that bores the electorate to tears yet splits the Conservative Party. Finally, to manage the transition of Britain’s primary military mission overseas from Iraq to Afghanistan in a way that does not allow the second struggle to become as unpopular at home as the first has become. That theme will be prominent in his Guildhall oration.

This is, however, an approach that – while understandable – is insufficient.

The next President of the United States will undoubtedly be more articulate than the current one (only Marcel Marceau could fail to meet that standard but he is (a) French, (b) dead and (c) thus not running for the Oval Office). This does not mean that the American view of the world will be transformed by Mr Bush’s departure. Rudy Giuliani and John McCain are no shrinking violets when it comes to the exercise of force and Hillary Clinton would be far tougher than her husband was.

Unless Iran engages in a spectacular and unlikely volte-face, then at some point in the next two years Washington will act to prevent Tehran acquiring nuclear weapons. British foreign policy has to be prepared for and predicated on that moment.

Neither tedium nor the Tories will be enough to neuter the EU treaty as an issue. Although I concede that it is not necessary for a referendum to be held, I wonder whether it is wise to resist one. Ministers underestimate their chances of winning. It could easily be turned into an “in or out?” argument. In many respects it is one. Membership of the EU brings with it, explicitly, the prospect of periodic bursts of integration. To complain about this is like going to a strip club and then protesting that you are offended by nudity. This is a brutal truth that should be confronted.

And a similar candour is demanded about Afghanistan. The Government is absolutely right to see this as a priority. It should also be honest enough, though, to declare that this engagement will make the deployment in Iraq appear straightforward. It will take far longer, it could involve substantially more casualties and there is no credible exit strategy other than victory. Public relations campaigns about the poppyfields do not alter any of these fundamentals. Voters are not being warned about the character of the sacrifices that this country will, because it must, be facing in Afghanistan for at least a decade.

All of this might be an irritation for a Prime Minister who awakes every morning full of zeal to deal with hardships in Kirby and Kilmarnock, not Kabul. Yet it is completely unavoidable. The Lord Mayor of London takes his position every November after an event described as the “silent ceremony” because barely a word is spoken throughout the proceedings. Silence is not an option in British foreign policy.

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