During his deadly attack on a packed Orlando nightclub where he killed 50 people and wounded many more, Omar Mateen called 911.  

On the recorded call, he pledge his loyalty to ISIS.  

A day later, a terrorist outside of Paris, used Facebook livestreaming to pledge his loyalty to ISIS while stabbing a police chief and his wife to death.

What's going on?

The answer is that these pledges aren't simply expressions of loyalty, they are expressions of fealty, a much more powerful means of connection.  

Fealty is something we haven't seen since the middle ages.  ISIS became capable of employing fealty once it rebuilt a barebones Caliphate and it is using it to transform modern terrorism.

To understand this, let's dig into fealty a bit. 

• Fealty is a strict, lifelong pledge of loyalty from a vassal to a lord.  It's public and irreversible.  (If you watch Game of Thrones, it's why everyone hates the Kingslayer, even if he was justified in his actions)
  
  
• Fealty obligates the vassal to act in the service of the lord, without any need for specific direction.  It also gives the protection of the lord to the vassal (in a religious context, salvation and redemption).
  
  
• Fealty made it possible to build large, geographically segmented networks in a world without instant communications and rapid travel.    

Fealty allows ISIS to get around some of problems of modern open source insurgency.   For example:

• A potential terrorist shouldn't express fealty until the attack.  Benefit: This prevents discovery during the grooming process.
  
  
• A public expression of fealty (FB, Twitter..) provides them with instant acceptance by the "lord"  Benefit: this provides them spiritual protection for the attack and maximizes the publicity for ISIS
  
  
• A Jihadi, or their local network, shouldn't ask for permission, planning, or support.  They should act on their own.  The attack itself is a demonstration of loyalty.  Benefit: this reduces chances of discovery and maximizes the innovative potential of the global network.

The more I think about it, fealty is an extremely useful way of harnessing and directing the power of an open source insurgency (aka, herding cats).