ISIS is online jihad 3.0. Dozens of Twitter accounts spread its message, and it has posted some major speeches in seven languages. Its videos borrow from Madison Avenue and Hollywood, from combat video games and cable television dramas, and its sensational dispatches are echoed and amplified on social media. When its accounts are blocked, new ones appear immediately. It also uses services like JustPaste to publish battle summaries, SoundCloud to release audio reports, Instagram to share images and WhatsApp to spread graphics and videos.
"They are very adept at targeting a young audience," said John G. Horgan, a psychologist at the University of Massachusetts at Lowell who has long studied terrorism. "There's an urgency: 'Be part of something that's bigger than yourself and be part of it now.' " Fawaz A. Gerges, a professor at the London School of Economics and the author of "The Far Enemy: Why Jihad Went Global," said ISIS had so far consistently focused on what militants call "the near enemy" — leaders of Muslim countries like Bashar al-Assad of Syria — and not "the far enemy" of the United States and Europe.
"The struggle against the Americans and the Israelis is distant, not a priority," he said. "It has to await liberation at home."
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Al Qaeda has often stressed the advantage to the terrorist network of supporters who hold Western passports and can attack in their countries. But a common public rite of passage for new recruits to ISIS is tearing up or burning their passports, signifying a no-going-back commitment to the Islamic state.
One polished ISIS video features a Canadian recruit named Andre Poulin urging North American Muslims to follow him — and even to bring their families. "You'd be very well taken care of here," he said in the video. "Your families would live here in safety, just like how it is back home. You know we have expanses of territory here in Syria."
In another English-language video pitch, a British fighter identified as Brother Abu Bara al-Hindi poses the call to jihad as a test for comfortable Westerners. "Are you willing to sacrifice the fat job you've got, the big car, the family?" he asks. Despite such luxuries, he says, "Living in the West, I know how you feel — in the heart you feel depressed." The Prophet Muhammad, he declares, said, "The cure for depression is jihad."
Such appeals provoke curiosity, and British fighters have answered hundreds of questions about joining ISIS on Ask.fm, a website, including what type of shoes to bring and whether toothbrushes are available. When asked what to do upon arriving in Turkey or Syria, the fighters often casually reply, "Kik me," referring to the instant messenger for smartphones, and continue the discussion in private.
The English-language videos do not soft-pedal the dangers of the fight; the video of Mr. Poulin, for instance, shows and celebrates his death in battle. But the message to English speakers is nonetheless far softer than the Arabic-language videos, which linger on enemy corpses and show handcuffed prisoners casually machine-gunned.
The message, said Mr. Gerges, is blunt: "Get out of the way or you will be crushed; join our caravan and make history."
Instead of emphasizing jihad as a means of personal fulfillment, the Arabic media production portrays it as duty for all Muslims. It flaunts violence toward its foes, especially Shiites and the Iraqi and Syrian security services, while portraying the killing as just vengeance.
A recent hourlong ISIS documentary opens with video shot from a drone over Falluja in Iraq and then over a convoy of ISIS gun trucks heading off to battle. A voice-over says that the Islamic state is expanding and that Jerusalem's Aqsa mosque is "only a stone's throw away."