(CNN) -- On Sunday, ISIS released a new audio recording calling for Muslims to kill Americans and Europeans. In it, an ISIS spokesman states, "If you can kill a disbelieving American or European, especially the spiteful and filthy French, or an Australian, or a Canadian or any other disbeliever, then rely upon Allah, and kill him in any manner or way however it may be." Last week's federal indictment against Mufid Elfgeeh provides a reminder of the potential for acts of violence by Americans inspired by al Qaeda's ideology that the new recording by ISIS seeks to exploit. Elfgeeh, a 30-year-old American citizen of Yemeni heritage who owns a pizza parlor in Rochester, New York, is accused of attempting to provide support to ISIS and planning to attack American soldiers.
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New report seeks to assess threat of terrorist attacks in the U.S.
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Peter Bergen says biggest risk is posed by individuals motivated by jihadist ideology
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Large-scale terror attacks such as 9/11 are less likely due to increased security, he says.
The difficulty al Qaeda and similar groups have had in inspiring Americans to conduct attacks at home is due to the strength of systemic security checks, such as the willingness of @placeholder communities to report potential terrorist activity.