Carl Bergen , David Brooks : First American soldier killed while fighting for ISIS . Abu-Salha had reportedly re-entered the United States after he received training from the group in Syria and before returning to the conflict . Writers : Other Americans drawn to ISIS , al - Qaeda in Syria ; 100 have fought or tried to . No American involved with ISIS or Nusra charged with plotting attack inside U.S. , they said . Writers : Tracking the foreign fighters is a key priority for our mission .
Carl Bergen , David Brooks : First American soldier killed while fighting for ISIS . Writers : Other Americans drawn to ISIS , al - Qaeda in Syria ; 100 have fought or tried to . No American involved with ISIS or Nusra charged with plotting attack inside U.S. , they said . Writers : Tracking the foreign fighters is a key priority for our mission .