The same is not true of Muslims. A minority of Muslim nations have a high level of religious toleration; for example Albania, Kosovo, Senegal and Sierra Leone. But a majority — including Saudi Arabia, Iran, Pakistan, Iraq and Malaysia — maintain strong restrictions on non-Muslim (and in some cases certain “heretical” Muslim) beliefs and practices. Although many Muslims think God’s will requires tolerance of false religious views, many do not.

A Pew Research Center poll in 2013 found that in Iraq, Malaysia, Pakistan and other nations in which Islam is officially favored, a large majority of Muslims think some form of Islamic law should be the law of the land. The poll also found that 76 percent of such Muslims in South Asia and 56 percent in the Middle East and North Africa favored executing Muslims who gave up their religion, and that in 10 Muslim counties at least 40 percent favored applying Islamic law to non-Muslims. This shows that, for many Muslims, the revealed truths of Islam are not only a matter of personal conviction but must also have a central place in the public sphere of a well-ordered society.

Does this mean that Islam is evil? No, but it does mean that it has not yet tamed, to the extent that Christianity has, the danger implicit in any religion that claims to be God’s own truth. To put it bluntly, Islam as a whole has not made the concessions to secular values that Christianity has. As President Obama recently said, “Some currents of Islam have not gone through a reformation that would help people adapt their religious doctrines to modernity.” This adaptation will be long and difficult and require many intellectual and socio-economic changes, some produced by outside forces, others arising from the increasing power of Islamic teachings on tolerance and love. But until such a transformation is achieved, it will be misleading to say that intolerance and violence are “a pure betrayal” of Islam.

There is no central religious authority or overwhelming consensus that excludes such Muslims from Islam. Intolerance need not lead to violence against nonbelievers; but, as we have seen, the logic of revelation readily moves in that direction unless interpretations of sacred texts are subject to nonreligious constraints. Islamic thinkers like Ibn-Sina accepted such constraints, and during the Middle Ages Muslims were often far more tolerant than Christians. But the path of modern tolerance has proved more difficult for Islam than for Christianity, and many Muslims still do not accept the ethical constraints that require religious tolerance, and a significant minority see violence against unbelievers as a divinely ordained duty. We may find it hard to believe that religious beliefs could motivate murders and insist that extreme violence is always due to mental instability or political fanaticism. But the logic (and the history) of religions tells against this view.