Scott Atran in Aeon:
Treating the Islamic State as merely a form of terrorism or violent extremism masks the menace. All novel developments are ‘extremist’ compared with what was the norm before. What matters for history is whether these movements survive and thrive against the competition. For our singularly self-predatory species, success has depended on willingness to shed blood, including the sacrifice of one’s own, not merely for family and tribe, wealth or status, but for some greater cause. This has been especially true since the start of the Axial Age more than two millennia ago. At that time, large-scale civilisations arose under the watchful gaze of powerful divinities, who mercilessly punished moral transgressors – thus ensuring that even strangers in multiethnic empires would work and fight as one.
Call it ‘god’ or whatever secular ideology one prefers, including any of the great modern salvational -isms: colonialism, socialism, anarchism, communism, fascism and liberalism. In Leviathan (1651), Thomas Hobbes deemed sacrifice for a transcendent ideal ‘the privilege of absurdity to which no creature but man is subject’. Humans make their greatest commitments and exertions, for ill or good, for the sake of ideas that give a sense of significance. In an inherently chaotic universe, where humans alone recognise that death is unavoidable, there is an overwhelming psychological impetus to overcome this tragedy of cognition: to realise ‘why I am’ and ‘who we are’.
In The Descent of Man (1871), Charles Darwin cast this devotion as the virtue of ‘morality… the spirit of patriotism, fidelity, obedience, courage, and sympathy’ with which winning groups are better endowed in history’s spiralling competition for survival and dominance. It is the sacred values, immune to material tradeoffs, that bind us most. In any culture, an unwillingness to sell out one’s kin or religious and political brotherhoods and motherlands is the line we usually will not cross. Devotion to these values can drive successes which are out of all proportion to expected outcomes.
More here.