If the 2001 plot by Jemaah Islamiah (JI) terrorists to attack Singapore had succeeded, the carnage could have been five times that of the horrendous Bali nightclub bomb blast a year later.
Painting this chilling scenario, terrorism expert Rohan Gunaratna says that over 1,000 people in Singapore might have been killed because of the sheer quantity of the explosives.
The terrorists planned to use six trucks, each loaded with three tonnes of ammonium nitrate, and simultaneously ram them into different targets in Singapore, according to a 2003 Singapore Government White Paper on the JI arrests and the threat of terrorism. In comparison, the terrorists who killed 202 civilians in Bali used a single Mitsubishi van packed with just over one tonne of potassium chlorate.
Potassium chlorate burns faster and is easier to turn into an explosive than ammonium nitrate.
Since the first wave of arrests of JI militants in Singapore in 2001, more than 60 men have been jailed for their involvement in planning terror attacks against Singapore. Of these, more than two-thirds have been released under orders restricting their movements.
The swift response of the Singapore authorities in using the country's tough anti-terrorism laws is one reason there has been no resurgence of the JI network in Singapore, says Dr Gunaratna, who has studied global terrorism threats for more than 25 years.
Other measures include the rehabilitation of JI detainees by Muslim clerics, and the forging of strong partnerships between the Government and the community.
But Singapore cannot afford to become complacent. Even with the best security measures in place, the United States and Britain have suffered terrorist attacks. Singapore's security system must be dynamic, retaining an element of unpredictability. "Terrorists are like pickpockets, always looking for gaps and loopholes in security systems to exploit," says Dr Gunaratna.
Terrorists are attempting to exploit weaknesses in security measures in many countries. In 2011, Malaysia repealed its Internal Security Act, a strict security law that let the government detain people without trial. The aim was to encourage the development of a modern and functioning democracy. But the authorities quickly realised that without this law, Malaysia's security was endangered.
To fill the vacuum, the Malaysian government last year introduced the Security Offences (Special Measures) Act, or Sosma.
But, the law has a downside. Malaysian terrorists who mount an attack outside the country cannot be prosecuted under the new legislation.
Dr Gunaratna cites the example of Yazid Sufaat, the alleged leader of Al-Qaeda in Malaysia. He could not be prosecuted for sending two operatives to fight in Syria with Al-Nusra, an Al-Qaeda-associated group.
Over in Indonesia, Densus 88, the country's elite anti-terrorism unit, has an effective strategy to catch, kill or otherwise disrupt terrorists and their activities. But Dr Gunaratna believes that Indonesia must also implement laws to ban terrorist groups and dismantle its infrastructure.
Unrepentant terrorists in jail must also be kept in isolation. This is currently not the case with Indonesian radical cleric Abu Bakar Bashir. Though locked up in a high-security prison in Nusakambangan in Indonesia, he can make phone calls, receive members of terrorist organisations and provide directions to his supporters. Dr Gunaratna also believes that jailed terrorists must be made to work. Each prisoner, he notes, costs countries around the world, about US$100 (S$126) a day.
Holding the title of Professor of Security Studies, the security expert heads the International Centre for Political Violence and Terrorism Research here. It was set up in 2002. Part of the S. Rajaratnam School of International Studies (RSIS), the centre generates data on the changing security landscape. It also advises security agencies on ways of crafting appropriate security responses.
Dr Gunaratna, 52, who obtained his PhD from St Andrews University, Scotland, became a much-sought-after expert after the 9/11 attacks. He also led a specialist team that built the United Nations database on Al-Qaeda.
The author and editor of 18 books on terrorism, he is a member of Israel's international advisory board for the International Institute of Counter-Terrorism.
The next phase in counter-terrorism work, says Dr Gunaratna, is to strengthen community engagement. "The public are the eyes and the ears of the government", he argues, noting that more than 80 per cent of counter-terrorism work is achieved through such efforts.
It was a hot lead from a Singaporean Muslim on the JI operations here in 2001 that alerted the Singapore authorities to terrorist plans. The informant revealed that, after the Sept 11, 2001 attacks in the US, Mohammad Aslam Yar Ali Khan, a Singaporean Muslim, boasted of his links with Al-Qaeda founder Osama bin Laden. Aslam also reportedly said he had been to battle in Afghanistan.
This tip-off started an intensive investigation by the Internal Security Department that led the authorities to uncover the JI clandestine network in Singapore.
To further reduce terrorist threats, Dr Gunaratna's terrorism research centre in RSIS is also helping security agencies in Indonesia, Pakistan and Afghanistan to build rehabilitation capabilities.
More significantly, the centre is mentoring younger officers to be "capacity builders and thought leaders". This year, three counter-terrorism officers received their PhDs while on attachment to RSIS.
One of them is the current Papua police chief Tito Karnavian. He was the former commander of Indonesia's Densus 88. The others are Muslim clerics in RSIS, Dr Muhammad Haniff Hassan and Dr Mohamed Ali.
Having interviewed dozens of terrorists detained in the US, Iraq and Asia, Dr Gunaratna says he understands the terrorist way of thinking.
"On the surface, they look just like us, normal. But it is very difficult to read their minds. They are very determined to use violence to achieve their political goals," he adds.
And, he warns, "they will give their lives for their cause".
This is a weekly series featuring people in the fight against terror.
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