But Mr Thaksin was no ordinary leader. In the end he represented an aberration that pushed a finely balanced system to its limits, forcing long-suppressed reactions.

A policeman who rose to become a billionaire, Mr Thaksin had come to dominate the once-splintered Thai political arena like no other leader. His party's reach extended into neutral audit bodies, such as the Senate, that were meant to limit his powers.

That backroom influence was matched by daring populist policies that won him two elections in a row. Even his opponents have been forced to admit that he had engaged the poor Thai countryside in a way no other politician had ever even conceived. Dirt-cheap health care, flexible loans to villages and a violent crackdown on drug dealers proved hugely popular in the areas where most Thai voters live, even as they alarmed the urban elite. If an election was held tomorrow, many believe Mr Thaksin would certainly win, if not by another landslide.

Yet such bold moves were accompanied by jarring political misjudgments.

First, there were the big decisions that even a populist like Mr Thaksin would struggle to reverse; the sale by his family of its controlling 49.6 per cent stake in the Shin Corp telecommunications empire to Singapore's government investment arm, Temasek. Then, as the outrage flared into widespread protest in Bangkok, came the decision to hold a snap election in April to renew his reputation and his mandate.

The provocative nature of the Shin Corp deal is hard to underestimate. Under Mr Thaksin, the firm grew fat on sweetheart government concessions. It controlled Thailand's only satellites. Shareholders were never consulted over the sale, nor was any tax paid. His family pocketed US$1.9 billion (not that this was strictly illegal; favourable tax-regulation changes had been raced through parliament shortly before the deal).

Then came the smaller, but ultimately fatal miscalculations. Among the last was his order on Tuesday for some of his most loyal military commanders to deploy three battalions - an estimated 2,000 men - of special warfare forces from Lopburi to the capital, nominally to guard against political violence amid protests planned for later in the week.

As he prepared to speak to the United Nations General Assembly in New York, he was already aware that a coup could be forming. He had tried to host a teleconference with his four top commanders at 8am on Tuesday (Thailand time). None had turned up, including the most powerful of them, army chief General Sondhi Boonyaratkalin. A talented and respected soldier and a Muslim, General Sondhi had been repeatedly and very publicly snubbed by Mr Thaksin, particularly over his recent plea for a more comprehensive plan to tackle the worsening Islamic insurgency in Thailand's troubled south.

Military sources say the special forces elements moved into the city at about 9pm, only to discover tanks had already been deployed around key points, including Mr Thaksin's formal seat of power, Government House. Word spread among the crack troops in red berets that Mr Thaksin was preparing to strip General Sondhi of his military power. Their decision was swift and easy, military sources have confirmed, as they started adding royal yellow streamers to their uniforms. General Sondhi was loyal to the king. He was also a former officer in the special forces, an elite group famous for its esprit de corps.

At 10.20pm, Mr Thaksin declared a state of emergency, sidelining General Sondhi in place of Thaksin loyalist General Ruengroj Mahasaranond, the man he had tasked to deploy the special forces hours before.

It was a final act of impotence by a leader without a capital after five years in power. General Sondhi was already in control and about to broadcast the first message from the junta through state media outlets. He was also in discussions with General Ruengroj, who by morning was at his side detailing the formation of their self-styled Council for Democratic Reform to 'strengthen' Thai democracy. There was an audience with the king, who provided an endorsement to the world.

For a politician long branded incorrigible and stubborn, Mr Thaksin appeared spent. He decided against using the unique platform of the UN's General Assembly and its audience of world leaders to rail against the forces of darkness denying his democratic rule. Instead, Mr Thaksin fled to London, and emerged from the Dorchester Hotel in a golf jacket to acknowledge he was 'jobless'.

'Underneath his stubbornness, he's always been a coward,' said one long-time political rival.

Unlike most of the 17 other coups that have littered modern Thai history, not a shot was fired. General Sondhi later revealed that he had been plotting the coup for two days, though he has yet to say what exactly was the catalyst for it. Days earlier he had again been denying coup rumours, saying the concept of a military takeover was 'obsolete' in modern Thailand.

Military and political sources asy the reality is more complex. While the detailed planning for the coup may have had an air of spontaneity, it had been brewing for months. Debate had been raging internally over repeated delays to the planned general election, Mr Thaksin's plans to promote loyal military officers in October's annual reshuffle, worsening violence in the south and, finally, his vague but unsettling comment that he was considering another 'rest'. Then came his claims of bomb threats on his life by military officers and of high-level plots against him.

As a turning point, the sources point to rare public appearances in July by the king's most valued adviser, Privy Councillor Prem Tinsulanonda. Mr Prem, a sprightly 86, is a retired military general who was appointed prime minister by the king in the 1980s and is himself a survivor of three coups.

Ever 'the king's soldier', Mr Prem appeared before army and naval cadets in full-dress uniform to tell them exactly where their loyalties lay. 'Horse owners hire jockeys to ride the horses,' he told the cadets at the Chulachomklao Royal Military Academy. 'The jockeys do not own the horses, they just ride them. A government is like a jockey. It supervises the soldiers, but the real owners are the country and the king.'

Two weeks later he repeated the sentiments to naval cadets, and warned of the need for national leaders to show high morality and ethics. 'There will be corruption, favouritism, nepotism and greed if leaders lack ethics and morals,' he said in remarks that got national attention. General Sondhi kept General Prem informed of the progress of Tuesday's events.

As Thailand reflects on a historic week, some believe it will not be its last coup, despite international diplomatic and business concern. Military interventions may be rare, one senior opposition figure suggested, but they may well happen, but, unlike the dark years before, they would be executed in the name of democracy. And therein lies the irony at the heart of Thailand's constitutional monarchy.