You might say that Castro and Guevara created plenty of incident for this evil, if you see the pictures of the firing squads in 1960s Cuba. It's not new, it's just transmutated and elevated into some kind of "art" or "science" by these barbarians.
There is a certain irony in the fact that Osama Bin Laden had his roots in Hadhramaut, in today's Yemen. Yet it is precisely in that region where moderate orthodox clerics, who are now part of the bulwark against extremism in Islam, have their roots.
Two such are Habib Ali Al-Jifri, who wrote this article, and Habib Umar bin Hafiz. Both are of Hadhramaut roots but live in the UAE, where they are patronised by the country's rulers. They represent the Shafi'i fiqh and the Ba Alawiyya Sufi order, dominant in the area and also spread to Saudi Arabia and the Gulf in no small part because of refugees who fled Communist rule in South Yemen.
Not only are Al-Jifri and Bin Hafiz renown ulama or scholars, they are also seen by the UAE as important assets in confronting extremism. The UAE, with good reason, has blacklisted the Muslim Brotherhood and CAIR, and other US and UK-based organisations which are extremist, yet tolerated and even indulged by the political class!
Yet the UAE also promotes the whole spectrum of Islamic orthodoxy as all four Sunni fiqhs are represented - the Maliki fiqh is dominant, but Hanafi, Shafi'i and Hanbali (aka Salafi/"Wahhabi") are also represented. In fairness, the Gulf states, Jordan and Egypt have a similar scenario. Even Saudi Arabia, by virtue of history, is more diverse in its makeup than would be assumed.
It is important to distinguish between traditional clerics who ally with legitimate authority, and radical clerics who preach revolution. The former belong to any of the four fiqhs or and two broad schools of theology. This is why clerics from two diametrically opposing versions of Sunni Islam - Sufism and Salafism - may be lumped together as "conservative" clerics because of their support for established order against revolution. And it is not only the Hanafi, Maliki and Shafi'i schools whose Ashari and Maturidi theology and Sufism constitutes the bulk of traditional Sunni Islam, but also the Hanbali fiqh and Salafist theology of Saudi Arabia (versions of it in Qatar and the UAE are actually milder in application). All of these are led by the traditional ulema who are educated and educate in the traditional Islamic manner.
Scholars from all of these schools, with their extensive networks of mosques and institutions, have devoted significant resources to denouncing ISIS with publications aimed at Muslims and non-Muslims alike.
For the Western world, engagement with Muslim rulers and establishment clerics may be the prudent thing to do as ISIS and extremism in general may not be defeated without them.