Special to WorldTribune.com

The Islamic State of Iraq and Levant horrified the West with its mass beheadings of hostages and used its notoriety to attract restless youth worldwide.

But such barbaric tactics is not what primarily concerns Navy Adm. William Gortney, commander of the Colorado-based U.S. Northern Command. Nor is the possibility that ISIL is sending fighters into the U.S. via a porous southern border.

The key threat posed by ISIL is the organization’s sophisticated social media recruiting campaign.

“I don’t believe that it’s [ISIL] that we have to worry about infiltrating through our southern approaches,” Adm. Gortney told reporters at the Pentagon on April 7.

“They are a threat to us because they’re using a very sophisticated social media campaign to incite American and Canadian citizens to do harm against American and Canadian citizens,” he said.

The FBI has launched a campaign to stop recruits in the U.S. from traveling to Syria and Iraq to join ISIL.

FBI Special Agent Andrew McCabe, head of the FBI’s Washington field office, said seven people in the past two weeks with ties to ISIL have been identified.

“It’s not hard to anticipate that, as numbers begin to grow, at some point our traditional investigative approaches and capabilities will be outstripped by the sheer numbers we’re facing,” Mr. McCabe told CBS News on Tuesday.

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