Manchester attack shows futility of the 'war on terror'

The suicide bomber attack on concert-goers in Manchester is ghastly and reminds us of the futility of the West's "war on terror".

Launched by President George W Bush as a doctrine after the 9/11 attacks, it has cost the US an estimated $2-trillion but now has little application in the modern landscape of terror.

The very concept of war is defined in international law with identifiable actors, most usually nation states. It includes limitations on the targeting of civilians and allows for war crime trials for those who break the rules.

All of this is absurd when the attacker is a person such as 22-year-old Salman Abedi who, before killing 22 people, had lived and was schooled among Mancunians.

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The Manchester attack echoes the Westminster attack in London in March in which 52-year-old Briton Khalid Masood drove a car through crowds, injuring 50 and killing four.

Intelligence experts point to a change in the tactics of al-Qaeda and the Islamic State which are urging radicalised loyalists to launch attacks in their home countries. Such threats are difficult to intercept, especially in democracies that respect civil liberties.

This new strategy also makes a mockery of attempts to harden national borders such as those attempted by US President Donald Trump.

It is clear that a greater threat lies within national borders rather than from without as the Manchester attack has illustrated.

This also brings into sharp focus the warning this week by the Institute for Security Studies that militant South Africans who have joined the Islamic State in the Middle East are likely to return home soon.

How we will deal with this potential threat should be a top priority of our intelligence services and, unfortunately, the lessons from the "war on terror" will offer little to help.