The latest terror attack, at an arena in Manchester, England, has claimed 22 lives so far and injured 59, including children and teens. Among the dead was an eight-year-old girl. The audience at the pop concert by 23-year-old singer Ariana Grande was dominated by millennials.

The suspect, Salman Abedi, 22, was of their generation too. Born and bred in Britain, he was just another face in the crowd, but this outwardly callow youth had plotted the death of innocents. He could be part of a group, which is why the terror threat level has been raised to "critical" in Britain.

The Manchester suicide bomber's attack has prompted measures to tighten security at major performances and sports events in the United States, Japan, Australia and elsewhere. That is only natural when terror strikes from out of the blue, often at ever-softer targets. In Pakistan, the faithful gathered in prayer were killed in 2013, and in France, families strolling down a promenade were mowed down last year. In Britain's case, it was still reeling from a chilling attack in March near the Palace of Westminster.

Fears tend to recede as time passes, and a state of alert might be stepped down. This, too, is natural as people want to return to a state of normalcy, as they should. Consequently, precautions that organisations or individuals might have undertaken by themselves could be outsourced in various degrees to state agencies or to private security providers.

For large events, for example, there is talk in some places of closer bag inspections, the use of metal detectors and even the deployment of search dogs. As queues lengthen, schedules get disrupted and costs multiply, and pressures could arise to cut some corners. When few or no incidents arise, complacency might well set in. It has been noted that in Singapore, checks at mass events are lax at times.

Worryingly, many organisations give little thought to how they would handle a potential terror strike. It is reckless to prepare after the fact, when there is already a grim litany from around the world of tragedies arising from terror attacks by lone wolves and organised groups.

Certainly, no preparation will ever be foolproof, but it is the responsibility of management to tackle terror risks as well, given the prevailing security climate. Groups must have contingency plans for the worst-case scenario so that people are not left in a state of confusion when major disruptions occur. Perimeter protection and access control are common enough.

But planning for emergencies and disaster recovery are also crucial. Apart from their great value in times of need, a nation's robust defences and responses can also serve to deter terrorists lurking in its midst.