(CNN) -- Over the past two years, 12 Americans have been charged with supporting militant groups fighting in Syria or have died while fighting with such groups. Who are they? Of the dozen Americans drawn to fight with ISIS or the al Qaeda affiliated Nusra Front, a profile does appear to be emerging: They are young, typically high school graduates and college students, who are self-recruited online by what they view as exciting video propaganda pouring out of ISIS and Nusra, and they seek to reach the Syrian battlefields by traveling via Turkey. The dozen Americans are a rainbow of ethnicities; of South Asian, East Asian, Caucasian, Middle Eastern and African-American descent, according to a survey by New America.
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12 Americans have been charged with supporting militant groups in Syria or have died there
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Peter Bergen: They are young, mostly not college grads, likely to have traveled through Turkey
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None is of Syrian descent; they represent a wide mix of ethnic backgrounds, he says
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Bergen: All but two of the 12 were active on jihadi social media
The importance of the @placeholder route into Syria likely provides the key to reduce the number of Americans traveling to fight in Syria.