Nothing says more about two countries and their relationship with each other than a good old-fashioned crisis. A state visit makes for nice photos; a cultural exchange is always more pleasant. But if you really want to know what two nations think about each other, and themselves, then only a full-blown international standoff will do. The capture of the 15 British sailors and marines has been a 12-day (so far) masterclass in them and us - even offering a few pointers as to how we might finally get along.
Start with us. A few days after the 15 were seized, I took a call from an Israeli journalist, wanting to know what on earth was going on with the British media. Why weren't photographs of the British captives on every front page, why weren't TV crews besieging the homes of their families? (This was before it emerged that one of those taken was a woman, Faye Turney, whose face rapidly appeared everywhere.) In Israel, he reminded me, the capture of a single soldier instantly becomes all-consuming, 24-hour news, the nation waiting for hourly updates. Yet, on the day we spoke, the story of the missing 15 did not appear on the front of a single British newspaper.
Perhaps, I suggested, that was because Britain, unlike Israel, does not have a conscript army: we do not see men and women in uniform as our collective sons and daughters, but rather as professionals who have chosen to take on a job, despite all its risks. But that, of course, cannot be the whole story. The US also has a volunteer army, yet if one of its soldiers is taken, it's only a matter of hours before America's trees, along with lapels and car bumpers, start sprouting yellow ribbons, demanding his release.
There's been next to none of that here. That may partly be because, with approval for the Iraq war at an all-time low, many Britons thought the Royal Navy had no business being there in the first place. Or it may be because we are still a more martial country than America, where public opinion, at least until 9/11, countenanced large-scale troop deployments reluctantly and rarely - demanding an exit as soon as things turned nasty, as they did in Somalia in 1993 - while we allowed Tony Blair to dispatch our forces to Kosovo, Sierra Leone and Afghanistan with barely a murmur of protest. The British public is, it seems, still fairly robust when it comes to military life and its costs.
Reaction to the conduct of the navy personnel themselves has been just as telling. Their unanimous, televised confessions to having entered Iranian waters struck the political right as proof that the British had lost their fabled backbone. "Whatever happened to name, rank and serial number?" asked the Daily Mail, furious that our boys (and girl) had not held their tongues and behaved like extras from The Great Escape. For the left, the ease of their confessions suggested the 15 were suffering from low morale, their faith in their Iraq mission so frail that it collapsed at the first push.
It's probably closer to the truth to suggest that the captives were simply using their common sense, saying whatever it took to placate their captors and stay safe. As for low morale, that's surely less relevant here than a form of arrogance bordering on incompetence on the part of British commanders, failing both to realise the risk of sailing so close to Iranian waters and, more specifically, to spot the Iranian craft hurtling towards the British boats. Still, none of that has stopped both left and right seeing what they want to see in this episode.
The Iranians have revealed just as much of themselves these past two weeks. First, they have offered a glimpse of the Anglophobia which - as the Guardian's Robert Tait reported in G2 - is deeply entrenched in Iranian culture, but which may come as a surprise to Britons, who tend to be more forgetful of our imperial past than those who lived at its sharp end. "They're obsessed by it," says Iranian specialist Dr Ali Ansari, noting that the resentment goes back not only to the British role in the 1953 coup which removed Iran's elected prime minister, but to the 19th century, when Britain used Iran as a protective buffer alongside India. While neighbouring Russia deployed hard military might, Britain has always relied on the blacker arts of power politics. Accordingly, says Ansari, "It's an easy sell in Iran to cast the English as the arch-manipulators."
So while we may see 15 luckless navy personnel who had strayed off course, the Iranians see the vanguard of the Inglisi, the cunning imperialists who are always behind Iran's problems. This is not just politicians' talk, it runs deep in the popular culture: witness the classic Iranian novel, My Uncle Napoleon, in which the lovable, Bonaparte-idolising patriarch sees British conspiracies everywhere. In this context, it's hardly surprising that the electronic scoreboard at last week's big football match in Tehran condemned not a border crossing, but the "Invasion of the British Forces to the Blue Waters of the Persian Gulf."
Which makes it no surprise that Iran would have seized the opportunity to inflict some pain on an old enemy, the Little Satan that is the crafty brain behind the big but blundering Great Satan of the United States. Iran, locked in a standoff over its nuclear ambitions, has enjoyed the chance to show London and Washington the finger. But not only us. Pictures of Turney and the rest were aired on Al-Alam, Tehran's Arabic-language station. That suggests Iran wanted to send a message to its Arab neighbours in the Gulf states, the Qatars and Kuwaits with whom relations are scratchy: if this is how we treat your patron - Britain - then imagine how we would treat you.
But the most crucial self-revelation has been Iran's confirmation that its government is a many-headed beast. The change in tone that came this week with the end of the new year celebrations, as cooler, foreign ministry types returned to their desks, illustrated the distance between them and the harder voices in the Revolutionary Guards and surrounding President Ahmadinejad. The fact that the president yesterday delayed a scheduled press conference for 24 hours suggests he was having to adapt to the more sober approach counselled by Ali Larijani, head of the supreme national security council.
Above all, this episode has shone a valuable light on the wider landscape. First, it leaves no doubt that Iran has emerged in the past four years as the decisive player (alongside Israel) in the region. As the patron of both Hamas and Hizbullah, and with its nuclear aspirations preoccupying the United States and the UN security council, it is Iran that is making the geopolitical weather. Credit for that belongs to George Bush and Tony Blair, whose war on terror removed Iran's biggest rival, Iraq, while handily knocking out the Taliban troublemakers in next-door Afghanistan. On the long list of disasters entailed by the Iraq calamity, the empowerment of Iran must rank very high indeed.
Yet the sailors crisis also offers a gleam of hope. If the rallying of those who favour engagement over confrontation does indeed bear fruit, and results in the captives' release, then it could set a useful precedent. There is already rising frustration with Ahmadinejad; the economy is stuttering, sanctions are beginning to hurt; zeal for a revolutionary battle with the west has faded. If moderates could also point to this crisis to show that talks with the west can yield results, there could be fresh impetus for the negotiations that matter - on Iran's nuclear plans. If that is right, then the old Chinese definition of the word "crisis" would be truly vindicated: that it is both a problem - and an opportunity.
Jonathan Freedland