ISLAMABAD: With one attack on September 11, 2001, Osama bin Laden put the “holy war” on the global agenda of the 21st century – and became a household name around the world.

As the world watched live on television, his al Qaeda militants flattened New York's World Trade Center, a devastating blow to the United States he loathed, and one that would have repercussions in every corner of the planet.

Nearly a decade after that attack, President Barack Obama on Sunday announced bin Laden's death, saying he was killed at his hideout in Pakistan and that US authorities had taken custody of his body.

The Saudi-born fundamentalist believed the carnage in 2001 – which left nearly 3,000 people dead – had been aided by God.

“America has been hit by Allah at its most vulnerable point,” he said.

Just as he had hoped, the hijacked planes that crashed into the Twin Towers as well as Washington and Pennsylvania ushered in a dramatic era of confrontation between the West and Islamic militants.

Though the attack made him the world's most wanted man, and forced him into hiding, it served as inspiration for a global jihadist movement that would grow far beyond any need for his guiding hand.

From the subsequent wars in Iraq and Afghanistan, to the 2005 attacks on London's transport system to the emboldened Islamic militants of Pakistan, much in the modern world seemed to flow from that one fateful Tuesday in America.

“We say that the end of the United States is imminent, whether bin Laden or his followers are alive or dead,” he said in a videotape message just four months after the attack.

“The awakening of the Muslim ummah (people) has occurred.”

'Like 1,000 days in an ordinary mosque'

There was little early sign the soft-spoken bin Laden, reckoned to have dozens of brothers and sisters in his vast and wealthy family, would one day be synonymous with global terror.

Born in Riyadh in 1957, exact date unknown, he was tall even as a youngster and stood about six-foot five (two metres) as an adult.

He took an engineering degree in 1975 and, though later remembered by those who knew him as always pious, his serious transformation took place four years later.

The year 1979 was a watershed for many young Muslims – the Iranian revolution, the Soviet invasion of Afghanistan and Egypt's peace treaty with Israel all helped radicalise a generation of frustrated believers.

Afghanistan became the first focus of his newfound idealism.

Inspired by the initial Muslim resistance to the Russian occupation, bin Laden started raising funds and recruiting fighters from across the Islamic world.

In 1984 he moved to the Pakistani city of Peshawar, a staging point for mainly Arab militants who – funded by the United States and Saudi Arabia, his future foes – fought jihad against the Soviets.

Stories abounded of the soft-spoken gentleman who visited the militant camps, spreading his largesse and encouraging weary fighters to press on with the battle.

“One day in Afghanistan is like one thousand days in an ordinary mosque,” Bin Laden said.

The eventual defeat and departure of the mighty Soviet army was seen as a glorious victory, and persuaded bin Laden not to disband the network of financiers and recruits ready to fight for Islam.

Instead, he soon found another cause to rally round back in Saudi Arabia, where the kingdom's rulers had allowed in US troops after Saddam Hussein's 1990 invasion of Kuwait.

The presence of infidel forces in the kingdom – home to Mecca and Medina, the holiest sites in Islam – galvanised his anger. His criticism of the monarchy was so bitter that he was expelled and his citizenship revoked.

Bin Laden then took his four wives and 10 children to Sudan, where a regime that was fighting an internal war against Christian and animist rebels was more than happy to welcome him.

In five years there he consolidated the operations of his group – dubbed al Qaeda, or The Base – and joined forces with Ayman al-Zawahiri, an Egyptian militant who became his deputy and later the “public face” of the organization.

Bin Laden left Sudan in 1996, around the same time that Western intelligence agencies began to link al Qaeda to attacks on US forces in Saudi Arabia and the failed Somalia operation recalled in “Black Hawk Down”.

His next stop was Afghanistan, where he found another group of supporters in the hardline Taliban.

'You'll see them and hear about them'

Bin Laden provided cash and fighters as the Taliban imposed their strict version of Islam on the country. In exchange, they let him run the training camps that would turn militant Islam into a global force to be reckoned with.

According to the official US 9/11 inquiry, the CIA estimated that as many as 20,000 militants trained in the camps before September 11.

In a 1997 interview with CNN, one of the few times he met Western reporters, bin Laden clearly stated his goals for all the world to hear.

"We declared jihad against the US government, because the US government is unjust, criminal and tyrannical," he said.

Peter Arnett, one of the journalists who conducted that interview, asked what bin Laden’s plans were.

"You’ll see them and hear about them in the media, God willing," he replied.

The world saw and heard on August 7, 1998, in al Qaeda’s first major international attack.

Powerful truck bombs outside the US embassies in Kenya and Tanzania killed 224 people, most of them Africans and many of them Muslims. Only 12 Americans were killed.

Bin Laden, who had no claims to be a religious scholar, used the Muslim faith to justify the bloodshed.

"When it becomes apparent that it would be impossible to repel these Americans without assaulting them, even if this involved the killings of Muslims, this is permissible under Islam," he said.

The US inquiry revealed that US authorities then considered air strikes on Afghanistan, where he was believed to be hiding, at least three times in 1998 and 1999 -- but each time top US officials opted against.

As one CIA official wrote: "We may well come to regret the decision not to go ahead."

Two years later, the September 11 attacks killed 2,739 people in New York, 189 people at the Pentagon and 40 passengers and crew on the flight that crashed in Pennsylvania.

The suicide operation was masterminded by Khalid Sheikh Mohammed -- who became one of the most famous of the US prisoners at Guantanamo Bay -- but had been personally approved by bin Laden, who selected the attackers.

As he had predicted, the United States struck back.

After the Taliban refused to hand bin Laden over, a US-led invasion toppled the Taliban from power.

But a massive manhunt for bin Laden, who had a bounty of 25 million dollars on his head, proved fruitless.

In the punishing mountain terrain along the Afghan and Pakistan border that had also defeated the Soviets, he could not be found.

'Jihad will continue'

Whether he would be captured and killed or not, bin Laden had fulfilled his life’s mission on 9/11 – galvanising Muslim militants worldwide in the struggle to make Islam one day reign supreme.

After the US invasion of Iraq, and widespread feeling that the war would not succeed in fighting "terrorism", some high-profile analysts stepped forward to challenge what had become the popular view of Bin Laden.

Michael Scheuer, the former head of the CIA unit dedicated to tracking bin Laden, argued that he had not been fighting the West in general but instead was at war with US policies – on Israel and Iraq – that had angered Muslims.

"The United States and its policies and actions are bin Laden’s only indispensable allies," Scheuer wrote in his book "Imperial Hubris".

Some critics within Islamic militant circles believed September 11 had been a strategic disaster. It led to the loss of the training camps in Afghanistan, brought down the Taliban and put the United States on high alert -- making future operations much more difficult to carry out.

But once the United States launched the war in Iraq in 2005, that perception largely changed.

The Iraq invasion rallied untold numbers of new jihadist fighters to the cause, and the country proved an ideal training ground for militants to hone their skills against the most well-equipped army in the world.

Some of the techniques developed there -- in particular the perfection of makeshift bombs or IEDs -- would soon be carried to Afghanistan and other theatres of jihad.

During his years on the run, bin Laden would have seen how his beliefs had caught fire with young and often angry idealists around the globe.

"Jihad will continue," he said not long after September 11. "Even if I am not around."