Just months ago, Mir Hossein Mousavi's name was unfamiliar to the millions of young Iranians who now hail him as a courageous leader after he openly defied the country's ultimate authority, Ayatollah Ali Khamenei, by demanding a new presidential election. Mr Mousavi warned that the electoral "cheating" that delivered President Mahmoud Ahmadinejad another four years in office threatens the very foundations of the Islamic republic. He vowed to stand by the side of all those seeking "new solutions" in a non-violent way.
His remarkable statement was issued on Saturday, a day after Ayatollah Khamenei, the supreme leader, ordered Mr Ahmadinejad's defeated challengers - Mr Mousavi foremost among them - to accept the outcome of the June 12 election. "He has dared to preach a counter-sermon to Khamenei's lecture on Islamic government," Gary Sick, a leading Iran expert at New York's Columbia University, wrote on his blog.
At the beginning of his election campaign, Mr Mousavi had appeared a grey, uninspiring and enigmatic figure. Now he is proving himself a resolute and confident man of steel, a prominent insider of the Islamic system forced into an opposition role. He has taken it, he argues, to defend the Islamic republic, of which he was a founding father. Mr Mousavi said in a statement on his newspaper's website: "We are not against our sacred system and its legal structures. This structure protects our independence, freedom and the Islamic republic." But, he added: "We are against deviation and lying and we seek to reform that, reform to return to the pure principles of the Islamic revolution."
Mr Mousavi called for freedom of expression in all its forms, saying that if the government permits people to express their views freely, "there won't be a need for the presence of military and regulatory forces in the streets". His statement was "revolutionary", Mr Sick wrote. "He views the fraudulent election as only the symptom of something far more serious. He describes a revolution gone wrong, a revolution that was originally based on attention to the voice of the people but has resulted in 'forcing an unwanted government on the nation'."
When Mr Mousavi entered the race for Iran's presidency, the bespectacled 67-year-old architect and accomplished amateur painter had been out of the political limelight for two decades after serving as prime minister during the ruinous war with Iraq in the 1980s. Mr Mousavi portrayed himself as a middle-ground leader determined to liberalise Iran's political and social systems by returning to the original principles of the 1979 Islamic Revolution.
Mr Mousavi's main attraction, at least in the early stages of his campaign, was that he was "anyone but Ahmadinejad". Many reformists had wanted their movement's main standard-bearer, the more charismatic former president, Mohammad Khatami, to lead their challenge to Mr Ahmadinejad at the polls. Mr Khatami, however, stood aside to support Mr Mousavi's campaign, believing he was better-placed to siphon off conservative votes from the president.
But in the final weeks of the election campaign Mr Mousavi's appearances with his charismatic wife, often holding hands, and the invention of the "green wave" resonated deeply with the Iranian public. Together the couple harnessed the aspirations of millions of Iranians longing for reform and their country's return to the international community as a respected member. Mr Mousavi succeeded in persuading disenchanted young people that their vote could make a difference. They were soon left furious and reeling by the election outcome.
"The extraordinary revulsion at the regime's electoral numbers left a leadership void. He [Mr Mousavi] stepped in, rather tentatively at first, and filled that role", Mr Sick wrote. "His top supporters and associates have already been jailed, and he could face the same fate - or worse." Iran's interior ministry on Saturday raised the distinct possibility of punishing Mr Mousavi, saying he would be "held responsible for the consequences of any illegal gatherings". He lost no time in raising the stakes by calling for a national strike if he is arrested.
The regime has the power to repress unrest on the streets but must know that dealing with a campaign of mass civil disobedience will be much more difficult. Mr Mousavi's followers - now a broad coalition of Iranians, from the most liberal-leaning reformists to religious conservatives - have started calling him "the Gandhi of Iran". He has repeatedly stressed that his challenge to the "stolen election" will be peaceful. He assured his followers on Saturday: "As a companion who has seen the beauties of your green wave, I will never allow anyone's life endangered because of my actions. By trust in God, and hope for the future, and leaning on the strength of social movements, claim your rights within the framework of the existing constitution, based on the principle of non-violence. Be sure that I will always stand with you."
In his defiance, Mr Mousavi is proving to have more grit and resourcefulness than Mr Khatami, whose attempts to liberalise the Islamic system during his eight years as president were thwarted by the old guard establishment, which had a grip on most levers of power. He never attempted to channel the frustrations of his disillusioned supporters into acts of civil disobedience. The post-election events have led to a bizarre situation in Iran. Mr Mousavi has the support, among others, of Mr Khatami, Mehdi Karrubi and Akbar Hashemi Rafsanjani, a powerful founding father of the Islamic republic. The three are leading politicians and clerics with impeccable revolutionary credentials. It "really boggles the mind" that they are now the "opposition", while Mr Ahmadinejad, his allies in the military together with "Iran's nascent military industrial complex" and Ayatollah Khamenei represent the "established order", said one Iranian analyst.
Perhaps Mr Mousavi's steeliness should come as no surprise. His mettle was tested in the hot seat when he served as Iran's prime minister from 1981 to 1989, a period spanning virtually the entirety of the devastating war with Iraq when he astutely managed the sanctions-hit economy. Ayatollah Khamenei was president at the time, and there was constant friction between them. Their ideologies and personalities clashed and both competed for the approval of the late Ayatollah Khomeini. Ayatollah Khamenei had even opposed Mr Mousavi's appointment as prime minister, mainly on economic grounds.
Mr Mousavi began his career as a hardliner. In the early 1980s, he supported Ayatollah Khomeini's drive to export the revolution, was an early supporter of Iran's nuclear programme and did not advocate free speech. Over the years he has evolved from a revolutionary into a pragmatic manager and reformer, believing, like many elders of the revolution, that radicalism must give way to peace and state-building.
Mr Sick wrote Mr Mousavi's statement on Saturday was effectively "a manifesto for a new vision of the Islamic republic". Now that his latent rivalry with Ayatollah Khamenei has erupted with unprecedented ferocity, Mr Mousavi, who has come to represent the democratic aspirations of the Iranian people, will be tested as never before. firstname.lastname@example.org