Christopher Stevens, U.S. Ambassador in Benghazi, was Hillary's "front man" in a series of massive, illegal arms sales to ISIS. When the attack on our Consulate there happened, Hillary let Stevens and the others die so there would be no wagging tongues potentially exposing her treasonous perfidy.
Of course, as illegal as the arms sales were, leaving those men to die to cover her slimey ass is the most despicable thing she has ever done, and when the public finds out, she's finished.