The Islamic State in Iraq and Syria (ISIS) may receive a damaging blow in the Middle East, as its largest Iraqi stronghold, the city of Mosul, may be retaken by Iraqi forces with coalition support.

But a defeat in Mosul will not put an end to the global ISIS threat. On the contrary, security analysts predict the terrorist group would re-emerge elsewhere to launch retaliatory strikes.

One hot spot is South-east Asia - including Singapore - as battle-hardened militants return home after fighting for ISIS in the Middle East.

The spectre of a looming attack prompted Singapore to hold an islandwide counter-terrorism exercise earlier this week. The danger level is at its highest ever, said Deputy Prime Minister Teo Chee Hean at the exercise, which involved more than 3,200 personnel from the police and Singapore Armed Forces.

The massive effort was not only to test the response of security agencies, but also to ensure ordinary Singaporeans understand the threat and, more importantly, know what to do in the event of an attack.The right thing to do, the police said, is to run to a safe place, hide and then inform them quickly of the attack.

Knowing these moves is critical, as was demonstrated at the exercise. It is a matter of life and death to keep to the minimum the time gap between an attack at, say, a shopping mall, and the arrival of first responders from the security forces.

The swifter people do the right thing, the smaller will be the death toll and number of people injured.

The exercise also helped to drive home, in a concrete way, the need for ordinary Singaporeans to stay vigilant and report to the authorities if they see anything suspicious.

No less important is the aftermath of a terror strike. The need for the community to rally together and stay united cannot be over-emphasised.

These various actions will not only decide whether a person lives or dies, but also whether the community can survive and rise above a terror attack.