– Driving hulking tanks and armored trucks, militants from the Islamic State in Iraq and the Levant (ISIL) conducted a victory parade of sorts recently in Raqqa, their stronghold in northern Syria, flaunting military hardware that they had captured.

Some of the masked fighters muscled the tanks into tight circles, spinning them around and around in front of a cheering crowd.

The startling imagery, posted on YouTube in June, not only raced across social media. It was also picked up by CNN and other TV networks, boosting the global profile of the Islamic State as it seeks to establish and violently expand its rule across much of the Middle East.

Before he was killed in 2011, Al-Qaida founder Osama bin Laden attempted to recruit and rally followers with pious sermons that now seem as dated as black-and-white TV. His aides had to secretly hand-deliver videotapes to Al Jazeera TV to get his words out.

Today, media-savvy militants in Iraq and Syria post graphic photos and slick recruitment videos on Facebook and Twitter, and even developed a now-defunct Android smartphone app that would automatically tweet from users' accounts. Fighters in the field answer questions from supporters on websites and chat rooms that allow users to remain anonymous.

"Back in the old days, jihadists would be depicted in recruiting photos with a rifle or a bomb," said Steven Stalinsky, executive director of the Middle East Media Research Institute, a nonprofit group based in Washington. "Now the laptop and handheld device are just as important."

Not surprisingly, the CIA is monitoring the Islamic State's use of social media, according to a spokesman.

"There are concerns about how the group is using these platforms for recruiting purposes to include targeting disenchanted Western youth," he said.

But social media also provide Western law enforcement and intelligence agencies with digital tools to help fight the group. Photos show captured weapons, provide tips about the location of training camps and massacre sites, and often make it easier to identify individuals, including Americans and other foreign fighters.

On Friday, the government of Britain warned that a terrorist attack is "highly likely" there because of the conflict in Syria and Iraq, and the hundreds of British and European citizens who have joined the Islamic State and other militant groups.

Analysts say the Islamic State propaganda campaign far exceeds that of Al-Qaida or any other recent U.S. adversary in its ability to recruit, raise money and instill fear in enemies.

The high-definition video of a masked militant beheading American journalist James Foley horrified many when it was posted on YouTube on Aug. 19.

The importance of the outreach was clear in a yearlong study of the social media profiles of 190 Western foreign fighters by the International Center for the Study of Radicalization and Political Violence at King's College London.

"For them, social media has come to represent both an essential source of information and inspiration," the report said. "It is clear to us that in the minds of foreign fighters, social media is not merely virtual: It has become an essential part of what happens on the ground."