The author might add that the Christian religion, especially the Protestant branch, was amenable to the "scrutiny of reason." The journey to that point was not without its setbacks and is by no means should be characterized as a straight line with each step one of unalloyed progress toward reason as defined by the Enlightenment. Modern Islam is simply not amenable to the same scrutiny.
Nevertheless, Christianity did ultimately arrive at a point at which it would tolerate the Enlightenment. The idea of individual salvation rather than group salvation no doubt accelerated the journey.
It is an absurdity to argue that Islam is anywhere near the state of toleration Christianity was at the time of the Scottish Enlightenment or the English Bill of Rights of 1688. Modern Islam, although a mixed bag in various parts of the earth, resembles more the Salem witch hunts or the zeal of the crusaders than it does the faith which led up to the ringing and sublime declarations contained in the announcement of American independence or in the faith which animated the Civil War after the Emancipation Proclamation.
Diversity is not our strength, but our Achilles' heel. Animosity to Christianity in the name of diversity is intolerance which smacks of a medieval tyranny over the mind in an attempt to save the soul.
Even reason can’t stand alone, any more than bookkeeping can. Both need a subject matter upon which to operate or are abstract, vain pursuits.
That's just one of the reasons Islam cannot be subjected to reason ~ they all believe all sorts of things that simply don't derive from Western religious traditions (Christianity, Judaism, Mithrism, Agnosticism, Polytheism) ~ their actual beliefs are more like disembodied animist spiritualism. Last thing any of these guys want to do is talk about sin and redemption ~
Not the churches that believe in a literal interpretation of the Bible. Evolution is off the table. Ditto other sciences that date anything older than about 6,000 years old and isotopic dating techniques.