The newly revealed cables show how leaders from around the world offered their unvarnished opinions about how to negotiate with, threaten and perhaps force Iran's leaders to renounce their atomic ambitions.

In late May 2009, Israel's Defence Minister, Ehud Barak, used a visit from a congressional delegation to send a pointed message to the new U.S. President.

In a secret cable sent back to Washington, the U.S. Ambassador to Israel, James Cunningham, reported that Mr. Barak had argued the world had six to 18 months “in which stopping Iran from acquiring nuclear weapons might still be viable.” After that, Mr. Barak said, “any military solution would result in unacceptable collateral damage.”

There was little surprising in Mr. Barak's implicit threat that Israel might attack Iran's nuclear facilities. As a pressure tactic, Israeli officials have been setting such deadlines, and extending them, for years. But six months later it was an Arab leader, the king of Bahrain, who provides the base for the U.S. 5th Fleet, telling the Americans that the Iranian nuclear programme “must be stopped,” according to another cable. “The danger of letting it go on is greater than the danger of stopping it,” he said.

His plea was shared by many of America's Arab allies, including the powerful King Abdullah of Saudi Arabia, who according to one cable repeatedly implored Washington to “cut off the head of the snake” while there was still time.

These warnings are part of a trove of diplomatic cables reaching back to the genesis of the Iranian nuclear standoff in which leaders from around the world offer their unvarnished opinions about how to negotiate with, threaten and perhaps force Iran's leaders to renounce their atomic ambitions.

The cables also contain a fresh U.S. intelligence assessment of Iran's missile programme. They reveal for the first time that the U.S. believes Iran has obtained advanced missiles from North Korea that could let it strike at Western European capitals and Moscow and help it develop more formidable long-range ballistic missiles.

In day-by-day detail, the cables, obtained by WikiLeaks and made available to a number of news organisations, tell the disparate diplomatic back stories of two administrations pressed from all sides to confront Tehran. They show how President George W. Bush, hamstrung by the complexities of Iraq and suspicions that he might attack Iran, struggled to put together even modest sanctions.

They also offer new insights into how President Barack Obama, determined to merge his promise of “engagement” with his vow to raise the pressure on the Iranians, assembled a coalition that agreed to impose an array of sanctions considerably harsher than any before attempted.

When Mr. Obama took office, many allies feared that his offers of engagement would make him appear weak to the Iranians. But the cables show how Mr. Obama's aides quickly countered those worries by rolling out a plan to encircle Iran with economic sanctions and anti-missile defences. In essence, the administration expected its outreach to fail, but believed it had to make a bona fide attempt in order to build support for tougher measures.

Feeding the administration's urgency was the intelligence about Iran's missile programme. As it weighed the implications of those findings, the administration manoeuvred to win Russian support for sanctions. It killed a Bush-era plan for a missile defence site in Poland which Moscow's leaders feared was directed at them, not Tehran and replaced it with one floating closer to Iran's coast. While the cables leave unclear whether there was an explicit quid pro quo, the move seems to have paid off.

There is also a U.S.-inspired plan to get the Saudis to offer China a steady oil supply, to wean it from energy dependence on Iran. The Saudis agreed, and insisted on iron-clad commitments from Beijing to join in sanctions against Tehran.

At the same time, the cables reveal how Iran's ascent has unified Israel and many long-time Arab adversaries notably the Saudis in a common cause. Publicly, these Arab states held their tongues, for fear of a domestic uproar and the retributions of a powerful neighbour. Privately, they clamoured for strong action by someone else.

If they seemed obsessed with Iran, though, they also seemed deeply conflicted about how to deal with it with diplomacy, covert action or force. In one typical cable, a senior Omani military officer is described as unable to decide what is worse: “a strike against Iran's nuclear capability and the resulting turmoil it would cause in the Gulf, or inaction and having to live with a nuclear-capable Iran.”

Still, running beneath the cables is a belief among many leaders that unless the current government in Tehran falls, Iran will have a bomb sooner or later. And the Obama administration appears doubtful that a military strike would change that.

One of the final cables, on February 12, 2010, recounts a lunch meeting in Paris between Herve Morin, then the French Defence Minister, and Secretary of Defence Robert Gates. Mr. Morin raised the delicate topic of whether Israel could strike Iran without U.S. support.

Mr. Gates responded “that he didn't know if they would be successful, but that Israel could carry out the operation.” Then he added a stark assessment: Any strike “would only delay Iranian plans by one to three years, while unifying the Iranian people to be forever embittered against the attacker.”

Fears of Arab states

In 2005, Iran abruptly abandoned an agreement with the Europeans and announced that it would resume uranium enrichment activities. As its programme grew, beginning with a handful of centrifuges, so, too, did many Arab states' fears of an Iranian bomb and exasperation over U.S. inability to block Tehran's progress.

To some extent, this Arab obsession with Iran was rooted in the uneasy sectarian division of the Muslim world, between the Shiites who rule Iran, and the Sunnis, who dominate most of the region. Those strains had been drawn tauter with the invasion of Iraq, which effectively transferred control of the government there from Sunni to Shiite leaders, many close to Iran.

In December 2005, the Saudi King expressed his anger that the Bush administration had ignored his advice against going to war. According to a cable from the U.S. Embassy in Riyadh, the King argued “that whereas in the past the U.S., Saudi Arabia and Saddam Hussein had agreed on the need to contain Iran, U.S. policy had now given Iraq to Iran as a ‘gift on a golden platter.'”

Regional distrust had only deepened with the election that year of a hardline Iranian President, Mahmoud Ahmadinejad.

During a meeting on December 27, 2005, with the Commander of the U.S. Central Command, General John Abizaid, military leaders from the United Arab Emirates “all agreed with Gen. Abizaid that Iran's new President Ahmadinejad seemed unbalanced, crazy even,” one cable reports. A few months later, the Emirates' defence chief, Crown Prince Mohammed bin Zayed of Abu Dhabi, told Gen. Abizaid that the U.S. needed to take action against Iran “this year or next.” The question was, what kind of action.

Previously, the crown prince had relayed the Emirates' fear that “it was only a matter of time before Israel or the U.S. would strike Iranian nuclear facility targets.” That could provoke an outcome the Emirates' leadership considered “catastrophic”: Iranian missile strikes on U.S. military installations in nearby countries like the Emirates.

Now, with Iran boasting in the spring of 2006 that it had successfully accomplished low-level uranium enrichment, the crown prince began to argue less equivocally, cables show. He stressed “that he wasn't suggesting that the first option was ‘bombing' Iran,” but also warned, “They have to be dealt with before they do something tragic.”

The Saudis, too, increased the pressure. In an April 2008 meeting with General David Petraeus, then the incoming Central Command chief, the Saudi Ambassador to Washington recalled the king's “frequent exhortations to the U.S. to attack Iran,” and the Foreign Minister said while he preferred economic pressure, the “use of military pressure against Iran should not be ruled out.”

Yet if the Persian Gulf allies were frustrated by American inaction, U.S. officials were equally frustrated by the Arabs' unwillingness to speak out against Iran. “We need our friends to say that they stand with the Americans,” Gen. Abizaid told Emirates officials, according to one cable.

Banks and business

Despite a U.S. trade embargo and several rounds of United Nations sanctions, the Bush administration had never forged the global coalition needed to impose truly painful international penalties on Iran. While France and Britain were supportive, countries such as Germany, Russia and China that traded extensively with Iran were reluctant, at best.

In the breach, the U.S. embarked on a campaign to convince foreign banks and companies it was in their interest to stop doing business with Iran, by demonstrating how Tehran used its banks, ships, planes and front companies to evade existing sanctions and feed its nuclear and missile programmes.

The cables show some notable moments of success, particularly with the banks. But they also make it clear that stopping Iran from obtaining needed technology was a maddening endeavour, with spies and money-laundering experts chasing shipments and transactions in whac-a-mole fashion, often to be stymied by recalcitrant foreign diplomats.

In Europe, Germany and others discerned an effort to grab market share. “According to the British, other EU member-states fear the U.S. is preparing to take commercial advantage of a new relationship with Iran and subsequently are slowing the EU sanctions process,” the U.S. Embassy in London reported.

The Obama administration, though, had a different strategy in mind.

New strategy

The man chosen to begin wiping out the confusion was Daniel Glaser, a little-known official with a title that took two breaths to enunciate in full: Acting Assistant Secretary of the Treasury for terrorist financing and financial crimes.

The first big rollout of his message appears to have come in Brussels on March 2-3, 2009, during what the cables called “an unprecedented classified briefing” to more than 70 Middle East experts from European governments.

Mr. Glaser got right to the point. Yes, engagement was part of the administration's overall strategy. “However, ‘engagement' alone is unlikely to succeed,” he said. And to those concerned the offer of reconciliation was open-ended, one cable said, he replied curtly that “time was not on our side.”

The relief among countries supporting sanctions was palpable enough to pierce the cables' smooth diplomatese. “Iran needs to fear the stick and feel a light ‘tap' now,” said Robert Cooper, a senior EU official.

“Glaser agreed, noting the stick could escalate beyond financial measures under a worst case scenario,” a cable said.

The Czechs were identified as surprisingly enthusiastic behind-the-scenes allies. Another section of the same cable was titled “Single Out but Understand the EU Foot-Draggers”: Sweden, considered something of a ringleader, followed by Cyprus, Greece, Luxembourg, Spain, Austria, Portugal and Romania.

The decoding of Mr. Obama's plan was apparently all that the Europeans needed, and by year's end, even Germany, with its suspicions and longstanding trading ties with Iran, appeared to be on board.

Still, there could be little meaningful action without Russia and China. Both are permanent members of the U.N. Security Council, where multilateral action would have to pass, and both possess a global reach that could effectively scuttle much of what the United States tried on its own.

The cables indicate the administration undertook multilayered diplomatic moves to help ensure that neither would cast a Council veto to protect Iran.

As of early 2010, China imported nearly 12 per cent of its oil from Iran and worried that supporting sanctions would imperil that supply. Obama administration officials have previously said that the year before, a senior adviser on Iran, Dennis B. Ross, travelled to Saudi Arabia to seek a guarantee it would supply the lost oil if China were cut off.

The cables show that Mr. Ross had indeed been in Riyadh, the Saudi capital, in April 2009. While there is no direct account of those meetings, a suggestion of dazzling success turns up later, in cables describing meetings between Saudi and Chinese officials.

The offer may have come during a January 13 meeting in Riyadh between Foreign Minister Yang Jiechi of China and Abdullah and other senior Saudi officials, one of whom told Yang, “Saudi Arabia understood China was concerned about having access to energy supplies, which could be cut off by Iran,” according to one cable.

The conversation, evidently shaped by Mr. Ross' request, developed from there, the cable indicated. A later cable noted simply, “Saudi Arabia has told the Chinese that it is willing to effectively trade a guaranteed oil supply in return for Chinese pressure on Iran not to develop nuclear weapons.”

That left Russia.

Dealing with Russia

Throughout 2009, the cables show, the Russians vehemently objected to U.S. plans for a ballistic missile defence site in Poland and the Czech Republic. Conceived under Mr. Bush and billed as a shield against long-range Iranian missiles that U.S. intelligence said were under development, the site was an irritant to Russia, which contended it was really designed to shoot down Russian missiles.

In talks with the U.S., the Russians insisted there would be no cooperation on other issues until the Eastern Europe site was scrapped. Those demands crested on July 29, when a senior Russian official repeatedly disrupted a meeting with Russia's objections, according to one cable.

Six weeks later, Mr. Obama gave the Russians what they wanted: He abruptly replaced the Eastern Europe site with a ship-borne system. That system, at least in its present form, is engineered to protect specific areas against short- and medium-range missiles, not pulverize long-range missiles soaring above the atmosphere. Mr. Obama explained the shift by saying that intelligence assessments had changed, and that the long-range missile threat appeared to be growing more slowly than previously thought.

The cables are silent on whether at some higher level, Russia hinted that Security Council action against Iran would be easier with the site gone.

Whatever the dynamic, Mr. Obama had removed the burr under the Russians' saddle, and in January 2010, one cable reported, a senior Russian official “indicated Russia's willingness to move to the pressure track.”

The cables obtained by WikiLeaks end in February 2010, before the last-minute manoeuvring that led to a fourth round of Security Council sanctions and even stiffer measures imposed by the U.S., the Europeans, Australia and Japan that experts say are beginning to pinch Iran's economy. But while Mr. Ahmadinejad has recently offered to resume nuclear negotiations, the cables underscore the extent to which Iran's true intentions remain a mystery.

As Prince Bin Zayed of Abu Dhabi put it in one cable: “Any culture that is patient and focussed enough to spend years working on a single carpet is capable of waiting years and even decades to achieve even greater goals.” His greatest worry, he said, “is not how much we know about Iran, but how much we don't.” — © New York Times News Service

(William J. Broad and Andrew W. Lehren contributed reporting)

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