Radical Islamists in Iraq are using social media to spread fear and propaganda in a way no terrorist group has done before.

Fighters from the Islamic State (also known as ISIL or ISIS) have shared Instagram pictures of gory executions, and have posted YouTube videos showing a beheading while tweeting "This is our ball. It’s made of skin #WorldCup." Seemingly without break, their Twitter accounts spew a mixture of carnage and preaching, peppered with weird jokes and gruesome taunts.

And American officials want them to keep it up.

An employee with a major social media company told Mashable that U.S. intelligence officials approached the company and asked that the ISIL accounts not be taken down, despite the often bloody and threatening content.

"U.S. intelligence prefers for these accounts to stay up, rather than come down," the employee said on condition that he and his company not be named.

The reason? American intelligence officials are monitoring the ISIL accounts, trying to glean information about the deadly group and its strengths, tactics and networks.

Social media "is one of the many sources" American analysts monitor when "assessing the fluid ISIL situation," a U.S. intelligence official told Mashable on condition of anonymity.

"Whether or not it makes more sense to be trying to quash this kind of communication so they can’t get their message out, intel folks would always want them to have it more open," said Jason Healey, a founding member of the Pentagon's first joint cyberwar unit and now director of the Atlantic Council's Statecraft Initiative.

Omar al-Shishani, a Chechen jihadist, among a group of ISIL fighters as they declare the elimination of the border between Iraq and Syria. The screenshot was taken from a video posted on a social media account frequently used for ISIL communications. Image: militant social media account via AP video/Associated Press

ISIL is the first international terror group to have embraced social media as a vital part of its identity. When they are not fighting, the militants tweet to no end, sharing pictures of captured weapons, taking over popular memes and tweeting about about their battle plans. In fact, their social media presence is so energetic, experts believe they are either quite naive about their exposure or their messages are part of a plan to inflate the group's power and popularize themselves amongst potential recruits.

"These guys are so busy promoting themselves online, you’d think they were Justin Bieber," Clint Watts, a senior fellow at the Foreign Policy Research Institute, told Mashable.

Certainly, the group appears to have a coordinated social media strategy, according to experts on intelligence gathering and the Middle East. As Kalev Leetaru, a fellow at Georgetown University, put it: ISIL is the first group to use "social media as an actual weapon of war."

Even so, social media is a double-edged sword since it allows U.S. analysts to discover things about the fighters they might not want to reveal.

"Right now I could get online and I could watch ISIL on social media and tell you where they are operating, which countries they’re from and who they’re working with," Watts said.

By studying social media feeds, American intelligence analysts can better understand what motivates ISIL fighters, the hierarchy of the organization and the ultimate aims of the group. As Watts told Mashable, ISIL fighters tweet about their plans and their leaders, and different factions of the group have ideological debates on Facebook.

If analysts know where to look, all they have to do is watch.

"There’s a lot of information that is being spread by ISIL accounts which could be used if the U.S. opts for drone attacks on Syria or Iraq," said intelligence expert Pieter Van Ostaeyen, who has been following ISIL tweets, which he says reveal a stunning amount. "They don’t seem to be afraid of anything being put out in the open. Or maybe they just don’t realize what they’re doing."

He cited an example from a few weeks ago, involving five British-born ISIL fighters, who went on Twitter to chat about meeting at a specific Syrian Internet cafe. When some of the other militants didn't show up as agreed, one of the fighters complained to the others on Twitter as if they were "in some private chatroom," Van Ostaeyen said.

Beyond such analysis of "open source" intelligence, U.S. officials are likely to have approached companies such as Facebook and Twitter to try to gain access to individual accounts, terrorism experts say. With that kind of access, agents could get information including the individual computer's IP address, using that to pinpoint the exact location of a fighter. Access to someone's Twitter account might also reveal an email address, which could lead to a new contact list for analysts to monitor.

Twitter and Facebook declined to comment for this article. YouTube, for its part, said that the company complies with "valid court orders and subpoenas," but declined to answer specific questions about ISIL.

Fighters from ISIL during a parade in Raqqa, Syria. Image: Raqqa Media Center/Associated Press

Though it might collect such information, the U.S. doesn't currently have a way to put it to use.

“Even if we were able to use the IP addresses, we’d have to be willing and able to deploy cyber tools, special ops and drones. And all three of those are currently imperfect responses to ISIL," said Tom Sanderson, a terrorism and intelligence expert at the Center for Strategic and International Studies.

Though the U.S. could pass information to the Iraqi government or even militias preparing to fight ISIL, Sanderson said he doesn't think the American government is about to do that. Information leaks to ISIL or an unfriendly government are too great a risk.

Spreading fear and propaganda, of course, is nothing new. The terror of Genghis Khan's campaign across Mongolia in the 12th century was a language of sorts: Heads on spikes communicated a clear message of pitilessness that helped crush opponents' spirits. Much later, al-Qaeda would found Inspire magazine to spread propaganda and its offshoot in Iraq would turn to televised beheadings to signal their willingness to commit unspeakably brutal acts.

Pic of fearsome Mujahid from Yemen. pic.twitter.com/DL98XGUHIo — Islamic State Media (@ISIS_Conquests) July 10, 2014

During the late 2000s, as al-Qaeda in Iraq was losing ground, decimated by both American forces and local Sunni tribes turning against them, the group clung to life — in part through social media, according to Watts. And just as the Internet was evolving from a series of static websites to a digital sphere fueled by connectivity, al-Qaeda was evolving as a network. The group took lessons learned about fighting, recruitment and propaganda in Iraq with them into Syria, where they emerged some years later as the Islamic State of Iraq and the Levant.

An influx of often young and tech savvy volunteers from the west has helped the group translate its message — not just linguistically but technologically and culturally through the appropriation of memes, for example — to a western audience. Yet there is something paradoxical about a group that wants to return everyone to the Dark Ages, yet uses high-tech American companies to disseminate that message.

In terms of how to respond, some terrorism experts think it might be worthwhile trying to shut down some of the more prolific accounts. But few really think it's a feasible task.

"These guys can move to so many new accounts on Twitter and Facebook," Sanderson told Mashable. "It’s just going to be an endless game of whack-a-mole."

"Extremists are on social media to stay," J.M. Berger, a researcher who focuses on extremists' use of social media, told Mashable. "And there's no putting the genie back in the bottle."

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