There are a number of good rules of thumb in life. One of them is don’t let a colorblind friend pick out your tie if you care what it looks like. Another is don’t take advice on religion from someone who is not particularly well-schooled or even observant in his own. In his most recent New York Times column David Brooks advises us that political violence in Islam can be eliminated by appealing to the Qur’an.
While possible I think that’s dubious. Jargon follows. Any religion or denomination that is sola scriptura and lacking in a magisterium will inherently allow for a wide variety of interpretations of scripture and some of those interpretations may be quite heterodox.
Both of those are the case with Islam and, consequently, Islam has even more variations in what is considered authentic belief than Christianity. That has also resulted in many Muslims being reluctant in the extreme to declare what is or is not authentic belief in Islam. Indeed, that’s one of the things that distinguishes the radical Islamists from others. They’re not reluctant at all. It’s why Pat Lang (and many others) refer to DAESH and Al Qaeda as takfiri, i.e. Muslims who accuse other Muslims of apostasy.
IMO non-Muslims arguing against radical Islam by citing the Qur’an is a sure formula for getting lost in the weeds. Muslims arguing against radical Islam by citing the Qur’an is already one of the “therapies” being tried to combat it. More of that is needed but we should recognize just how reluctant many Muslims are to criticize another Muslim’s beliefs.