If we exclude divine favor as an explanation of this long advance, as Christians and post-Christian secularists presumably should, the rules that explain it include capital punishment for leaving Islam (a.k.a. apostasy), which is presumably a disincentive to doing so; strict rules for regular public prayer, which strengthen group solidarity; a privileged position for men over women, amounting in practice to ownership of them as either wives or concubines; a hierarchical structure within Islamic society that places Muslims in a position above non-Muslims in law, government, and social life; and a religious orthodoxy that endows Muslims with a general superiority (and sense of superiority) over others in non-Islamic societies.

Taken together, these rules help to shape a Muslim community that is cohesive, conscious of its separation from the rest of society, resistant to influences likely to undermine its cohesion, self-policing through its male members, and — because its sense of superiority is not reflected in its actual status either locally or globally — prey to resentment and hostility toward those whom it blames for its unjust subordination.

That said, the minority that supports aggressive jihadism (or is simply contemptuous of non-Muslim society) is not just larger but, as opinion polls show, far larger than similar tendencies in other religions and ideologies. That minority seeks to impose its rules both on fellow Muslims and on the wider society. And it has had remarkable success in areas where Muslims predominate locally, making U.K. state schools conform to Islamic teaching and practices, including the separation of the sexes; establishing “no-go areas” of European cities where police go only by agreement and where in their absence Muslim rules on alcohol and modest female dress are enforced by violence; and turning local governments into reliable Muslim fiefdoms through levels of voter fraud not known in England since the mid-19th century.