One type of victim that is not carefully counted in the current outbreak of Islamic terrorism are Islamic clerics (including scholars) who are murdered by the terrorists for preaching against misuse of Islam to justify the violence. Al Qaeda and ISIL (Islamic State in Iraq and the Levant) were particularly diligent about this as well as killing Moslems in general who opposed them. Nearly all the victims of Islamic terrorism since the 1990s (when al Qaeda turned to Western nations) have been Moslems, most of them in Moslem majority nations. Even when Western forces are involved in fighting Islamic terrorists in a Moslem majority nation most (as in over 90 percent) of the deaths are because of Islamic terrorists killing Moslems who opposed hem. Al Qaeda also maintained that any Moslem killed during a terrorist attack, who didn't want to be, was simply an "involuntary martyr." While nice in theory the families of these involuntary martyrs hated al Qaeda for the honor and while al Qaeda leaders (like bin Laden) picked up on and ordered a change in tactics. This effort, begun about 2005 found many of their followers resistant to the change. Many Islamic terrorist leaders refused and one result was a more murderous version of al Qaeda in the form of ISIL. This meant there was justifications for making attacks on mosques, religious schools and so on if there was a cleric or scholar there preaching against that very kind of violence.
By 2014 even the most senior and respected religious scholars, like the Egyptian Grand Mufti Shawqi Alla, denounced ISIL, in large part because of their murderous attitude towards any criticism by anyone Moslem or non-Moslem, with no exceptions for Moslem clerics and holy places and especially not for involuntary martyrs. While Islamic scripture clearly banned involuntary martyrs it also was unclear about who could decide, for all Moslems, what was the only correct way of praying. This was best exemplified by the explicit obligation for all Moslems to make the haj, or pilgrimage to Mecca and the general agreement that all Moslems were welcome. Yet the rest of the year these differences could be seen as a reason to kill a fellow Moslem.
At that point the well-guarded Grand Mufti was just another ISIL critic on an already long list of religious scholars risking their lives to denounce this murderous and vindictive group. ISIL regularly reminds everyone that any cleric preaching against the group is considered to be un-Islamic and subject to attack by ISIL death squads. When ISIL shows up in an area the clerics become a lot more discreet in their criticism, often to the point of silence about ISIL or else a quick departure to a safer location. But it isn’t just ISIL. More “moderate” terror groups like the Taliban (in Afghanistan and Pakistan), Boko Haram (in Nigeria) and al Shabaab (in Somalia) will concentrate their efforts on clerics who oppose them, but prefer death squads or bombs placed in the clerics car rather than mass slaughter in crowded Mosques. In addition to all those murders there are many more death-threats delivered, in addition to physical beatings and kidnapping.
These less lethal methods are more popular in the West, and continue to this day. Even then there are occasional clerics murdered. When that happens in the West most Moslems will refrain from discussing this with non-Moslems, especially the police. Throughout the Islamic world there is a reluctance to even compile the number of clerics killed by this or subjected to death threats.
Islamic radicalism has been trapped in a self-destructive cycle of its own making for over a thousand years. It works like this. Islamic radicals obtain their popularity and power by proclaiming that they are defending Islam from non-believers and sinners (usually within the Islamic community, often local Moslem dictators). In order to maintain this moral superiority, the Islamic radicals must be better Moslems, and insist that others do as they do. Since Islam is a religion that dictates how one lives, in considerable detail, as well as how one prays, this business of being a "good Moslem" can get tricky. And it is. There's a race underway by Islamic radicals, and the clergy that provide theological support, to issue, and enforce, more and more rules on how a good Moslem should live. These rules often contradict each other, with murderous results to all concerned.
For example, back in 2009 a Saudi Islamic scholar issued a fatwa (a religious ruling by a qualified religious official, although unqualified clergy can try to issue these and hope that people will obey) banning the use of alcohol as a substitute for petroleum in vehicle fuel. The reasoning was that the Koran forbids the use of alcohol for any use, not just for drinking. The fatwa applies to all Moslems, everywhere and more radical Moslems believe it is their duty to enforce the rule with the death penalty.
At the same time the Indonesian council of Islamic Clerics, the senior fatwa issuing authority in that country, issued a number of interesting fatwas. One banned smoking in public, or by children or pregnant women under any circumstances. Another allowed men to marry child brides (as young as 9). That one might be a problem, as Indonesian civil law makes it illegal to marry a woman under the age of 18. Islamic clerics justify this because the Prophet Mohammed consummated his marriage to a nine year old. The sex with minors thing has been going on in Indonesia, with the assent of the clergy, for years, and only became an issue when a clerical group sought to have the civil law changed to make such activities legal.
Meanwhile, in Saudi Arabia, civil and religious officials are arguing over the same issue. The clergy are arguing among themselves over the idea of marrying young girls, and civil officials oppose this sort of thing, even though many Saudi men are for it. This is particularly tricky for the image of Islam. Living according to the Koran, and rules drawn up in 7th century Arabia from contemporary customs ignores over a thousand years of social, medical and scholarly progress. Most of the world, including most Moslems, have embraced the modern world and have no interest in dialing back from the 21st century to the 7th.
The problem with controversial issues like this is that, once enough clergy get behind some lifestyle rules, they also grant permission for religious vigilantes to use force to enforce these rules. Saudi Arabia and Iran have lifestyle police that can arrest, and imprison you. The “God Squad” can also use force to restrain (arrest) offenders, and often do. In Saudi Arabia, this had gotten so bad that at one point the king fired the head of the religious police. There were growing complaints from the public about the rough treatment they were getting from the religious cops, and the king agreed that things had gone too far. But few rulers of Moslem nations have the power and authority of the Saudi king. The Sauds are admired for ruling the longest-lasting state using strictly applied sharia (Islamic law). That means no houses of worship except Moslem ones and no public religious ceremonies other than Moslem ones. Even then there have always been Moslem clerics who complain, as openly as they dare, that the Sauds are not strict enough. When these critics go public they are shot down, sometimes with great difficulty, by police and soldiers (usually from the tribal National Guard) who are loyal to the House of Saud.
The Saudis manage to pull this off by devoting most of oil wealth they have received since the 1930s to reward those who are faithful to the Sauds. This is done as an alternative to building a self-sustaining economy, one that will survive the time when they run out of oil or technology (like fracking right now and eventually fusion power). To keep the peace with Islamic conservatives the Sauds turned the educational system over to loyal (but very conservative) clerics who emphasized studying religion and downplaying technology of any sort. This meant most Sauds came of age unprepared to survive in the modern world. No problem, the Saudis and other oil rich Arabian nations imported workers, including technical personnel and administrators to do that work. Non-Moslems were preferred lest foreign Moslems become disloyal to the king. This was not just paranoia. The Palestinians proved disloyal as did many of the Yemenis allowed into Saudi Arabia because they came from the one Arabian state with hardly any oil. It is telling that the Arab oil states have refused (as much as they can get away with) to accept Moslem refugees from wars that involve Islamic terrorism. Let the West take them because true Moslems know better.
In non-Arab Moslem states with little in the way of exportable natural resources these “Arab” attitudes are often popular in theory but hated in practice. In the late 1990s, the Taliban in Afghanistan made themselves so unpopular with the use of their lifestyle police that they lost control of the country in less than 90 days after the U.S. intervened in the civil war (against some northern tribes who had not yet been conquered by the Taliban) with a few hundred American Special Forces troops and CIA operatives (and a few hundred smart bombs).
The Islamic radicals have not come up with a way to avoid this trap. Every time the Islamic radicals gain power, they begin implementing stricter, and sometimes absurd (even to many of the locals) lifestyle rules. When the radicals try to enforce all these rules, the people eventually push back, and the religious dictatorship falls. Eventually (after a few generations) another Islamic radical movement develops and the cycle repeats itself.