PARIS — The revelation that the 29-year-old man who opened fire on Sunday in a gay nightclub had dedicated the killing to the Islamic State has prompted a now familiar question: Was the killer truly acting under orders from the Islamic State, or just seeking publicity and the group's approval for a personal act of hate?
For the terror planners of the Islamic State, the difference is mostly irrelevant.
Influencing distant attackers to pledge allegiance to the Islamic State and then carry out mass murder has become a core part of the group's propaganda over the past two years. It is a purposeful blurring of the line between operations that are planned and carried out by the terror group's core fighters and those carried out by its sympathizers.
The attacker, Omar Mateen, told a 911 operator that he was pledging allegiance to the Islamic State. That pledge is a central part of the ISIS protocol. The Orlando killing was the third time the loyalty pledge was known to be invoked in the United States.
In December, when a couple in San Bernardino, California, left their home armed with assault rifles, they made sure to post their oath of allegiance on Facebook, where law enforcement agents later found it. And just minutes before he opened fire on a cartoon exhibit featuring images of the Prophet Muhammad in Texas in May 2015, Elton Simpson sent out a series of Twitter messages making clear where his allegiances lay.
This public oath is about the only requirement that the Islamic State imposes on followers who wish to carry out acts of terror in its name. In an annual speech last month, the terror group's spokesman, Abu Muhammad al-Adnani, incited its supporters to carry out killings abroad during the holy month of Ramadan.
No attack is too small, he advised, specifically naming the United States as a target. "The smallest action you do in the heart of their land is dearer to us than the largest action by us," he said, "and more effective and more damaging to them."
[What happened at the Orlando nightclub shooting]
As early as September 2014, Adnani made clear that anyone and everyone could, and should, carry out acts of terror in the group's name. "Do not ask for anyone's permission," he said, and suggested that sympathizers who could not buy weapons should instead use rocks, knives or even cars to kill infidels.
Since then, the group has worked hard to create a mechanism for inciting terror in situ. It floods the internet with gory propaganda and employs an army of keyboard jihadis to push the deadly message on Twitter, Facebook and other social media.
In this case, there was a stark resonance between Islamic State propaganda and the killer's choice of target. The jihadi group has publicized its hatred of homosexuality, including releasing images of fighters killing people suspected of being gay by throwing them off tall buildings.
Once the recruit is caught, or killed, law enforcement officials struggle to put the pieces together. Yet the fact that there is often no direct link back to the core is intended to protect the organization in an age of surveillance.
"I think what the Islamic State has done is very clever, and that is create a situation where someone can carry out an attack without any direct link to the organization," said Charlie Winter, senior research associate at Georgia State University's Transcultural Conflict and Violence Initiative. "They can pledge allegiance to Abu Bakr al-Baghdadi before or during, and that catapults them from being a self-starter jihadist guy, or girl, to someone who can be lionized as a soldier of the Islamic State and regarded as a warrior."
On Sunday, after it was known that Mateen had invoked ISIS, the group's official news agency issued a bulletin quoting "a source" confirming that Mateen was acting on the Islamic State's behalf.
Jihadis erupted in celebration on the internet. They shared screenshots of Adnani's speech calling for lone wolf attacks during Ramadan. And in an act of tribute, several changed their profile pictures on Twitter to a photograph of the Orlando attacker.