The studied sadism with which American journalist James Foley was beheaded by the Islamic State in Iraq and Syria (ISIS) last week reveals the true character of a terror outfit that has arrogated to itself the task of setting up a global Muslim caliphate.
Few would be attracted by its doctrinal claims, but fewer would disregard its capacity for mayhem if it is not stopped swiftly. The group's methods are so extreme that it was expelled even from Al-Qaeda.
Mr Foley's execution, one of the many egregious acts of violence which ISIS has perpetrated, will confirm its reputation for extremism that even other terrorists find extreme.
The release of the gruesome video of Mr Foley's decapitation will not advance its cause of appealing to Muslim opinion, but that was not its intention. The video is a warning to countries of what will happen to their captured citizens if demands for ransom are not met.
Given that kidnapping foreigners is a fairly prominent part of the business model of terrorist organisations - Al-Qaeda and its affiliates are estimated to have earned at least US$125 million (S$156 million) in ransom payments in the past five years - this was a way of making a point to the US, which refused to pay the ransom demanded for Mr Foley's release.
Prisoner swops are another part of the hostage-taking strategy. Like turning down ransom demands, rebuffing swop offers is an important way of undermining terrorist tactics. However, as Mr Foley's case shows, the consequences can be traumatic.
Yet, the brand of terrorism practised by ISIS has galvanised international opinion against it. The United States has declared its determination to deal with a scourge that can violently unravel the Arab regional order, impinge on religious relations in Europe - from where many foreign ISIS jihadists are drawn - and affect developments far beyond both regions.
The draw of the militant group's all-or-nothing ideology, in which the world is divided implacably between believers and infidels, extends into South-east Asia as well. Much as Al-Qaeda once enticed citizens in eclectic and tolerant societies to abjure their local cultures and traditions and join its global fight to the death against the West, ISIS has the potential to threaten South-east Asia with another round of jihadist internationalism.
The US, a primary upholder of the secular world order, must ensure that ISIS does not use the Middle East as a bridgehead for its project of holding the world to ransom.
In South-east Asia, national and religious leaders and all people of goodwill must act and speak out strongly against this latest threat to the human capacity to live together in spite of religious differences. Let it be clear: This barbarity has nothing to do with any religion.
This article was published on Aug 25 in The Straits Times.
Get a copy of The Straits Times or go to straitstimes.com for more stories.