The ISIS Caliphate is using online fealty as a way to recruit jihadis around the world. It's a powerful recasting of an ancient concept that goes well beyond modern expressions of loyalty.
The way ISIS has constructed its brand of online fealty makes it globally scalable. The only barriers to entry are: conduct an attack and publicly pledge fealty. The most common platforms for a public pledge? Social media, 911, etc.
For example, when Omar Mateen pledged fealty to ISIS during his deadly attack, it provided him with the following:
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