The lessons of 2004 worked again in 2007.
The release of 15 British naval personnel Wednesday, coming after several days of intensified negotiations, was welcomed in Britain as evidence that a "softly, softly" approach could prove effective with Iran – as it did in a similar prisoner crisis three years ago.
"This is vindication for the British diplomats, who came under a lot of criticism," says Ali Ansari, an Iran expert at London's Chatham house think tank. "Diplomacy worked. People should reflect on this: There are diplomatic options when we deal with Iran. It's a very salutary lesson."
After a 13-day standoff, Iranian President Mahmoud Ahmadinejad held a press conference in Tehran and praised the Iranian Coast Guard who had "courageously defended" Iran's territorial waters. Then he "pardoned" the prisoners as an Easter gift to Britain.
Some saw it as a lesson with historical precedence. Earlier this week, Hodding Carter III, who was US undersecretary of State during the 1979-81 hostage crisis, said one of the conclusions to be drawn was that "when hostages are taken it's a very good time for governments to shut up."
"You're better off conducting diplomacy behind closed doors," he told BBC radio Monday. "You are far more likely to be able to affect something if you are not out there beating your chest and letting them beat their chest in return."
British diplomats had essentially been trying to do just that in recent days: working quietly to elaborate a formula that will enable both sides to emerge with no loss of face. Despite shrill calls from Americans such as former US ambassador to the UN, John Bolton, and from parts of the domestic press to act more robustly against Iran, Britain by and large pursued a diplomatic approach.
After almost two weeks of mutual recrimination, signs first emerged Monday that diplomacy was making headway.
Ali Larijani, Iran's influential national security council chief, said Monday Tehran wanted to resolve the issue diplomatically and did not want drawn-out "complications."
British Prime Minister Tony Blair for his part said Mr. Larijani's comments "seem to offer some prospect," and said the door was open to a diplomatic resolution.
Foreign Secretary Margaret Beckett said Tuesday evening that there was a "huge amount" going on behind the scenes.
"There are still some differences between us, but we share [Larijani's] preference for early bilateral discussions to find a diplomatic solution to this problem," one British official told the Monitor, on customary condition of anonymity.
Indeed, said experts, such an approach would more likely to lead to a solution.
"What is to be gained from following the Israeli example of last summer [when it invaded Lebanon after its soldier was captured]?" asks Rosemary Hollis, a Middle East expert also at Chatham House, "You can't use a sledgehammer to crack a nut. They still haven't got their service personnel back, and they smashed up half of Lebanon."
The key in such situations is to find "a formula which both sides can benefit from, says Dr. Hollis.
That was the approach in 2004, when six British sailors and marines were seized in a similar part of the Persian Gulf, Britain took a face-saving approach, quietly admitting that its personnel may have strayed across the border by mistake.
This time around, however, there was intense discussion in London about how hard-line Britain's approach should be, says Dr. Ansari. But in the end, those advocating for diplomacy – in both Iran and Britain – triumphed, he says. "I think the battle was won on both sides [Iranian and British] by those saying 'We have to take this with firm resolve, but with a diplomatic approach.'
Hollis at Chatham House, adds: "The ingredients for a diplomatic solution have always been present, but it took a senior figure in Tehran to clarify that that was also what they were looking for, and how to proceed."
But other analysts were more critical of the resolution.
"[The Iranians] have pulled off a significant propaganda coup," says Major (ret.) Charles Heyman, a British defense expert. "There's a subtext to this – that we [the Iranians] are the innocent party, and we are behaving as rational and decent people. What they're really saying is, 'We're a joined up member of the international community whether you like it or not.' It's very difficult for us to respond to it other than by saying thank you – very difficult."
Ahmadinejad's announcement came after Iran's state media reported that an Iranian envoy would be allowed to meet five Iranians detained by US forces in northern Iraq. Another Iranian diplomat, separately seized two months ago by uniformed gunmen in Iraq, was released and returned Tuesday to Tehran. But Ahmadinejad said there was no connection to the release of the Britons.
"If we had wanted to exchange Jalal Sharafi with the rest [the Britons] we would have exchanged him for 100,000 [people]. But we pardoned them," he said, adding the decision was "based on humanitarian considerations."
After his announcement, crude oil prices slipped. Oil futures had surged 7 percent, to above $64 a barrel, since the sailors were taken hostage on March 23.
Ahmadinejad said the British government had sent a letter to the Iranian Foreign Ministry pledging that entering Iranian waters "will not happen again."
In his press conference, Ahmadinejad said, "On the occasion of the birthday of the great prophet [Muhammad] ... and for the occasion of the passing of Christ, I say the Islamic Republic government and the Iranian people – with all powers and legal right to put the soldiers on trial – forgave those 15," he said, referring to the Muslim prophet's birthday on March 30 and the Easter holiday. "This pardon is a gift to the British people," he said.
The family of British Royal Marine Adam Sperry hailed the announcement as "the best present imaginable".
"The one thing I wanted was Adam's safe return to his family for Easter," Mr. Sperry's uncle, Ray Cooper, told the Associated Press. "Whoever has been in the right or wrong, the whole thing has been a political mess, so let's just get them home. It's great."
• Christa Case contributed reporting from Boston. Material from wire services was also used in this report.