Simply warmongering to say otherwise.
For its part, in Gaza, Hamas does not kill Christians; indeed they worship freely, are represented in the government, and share in the bitter and blockaded status of Gaza’s Muslims. Hamas doesn’t aspire to a Muslim caliphate but rather national liberation, and, if you follow the contemporary words of its spokesman, (rather than its generation old, anti-Semitic charter) liberation of a small part of historic Palestine. Hamas doesn’t execute Western journalists but welcomes them. It does execute suspected collaborators (that’s where the gruesome execution photos which Israel-friendly organizations have been using in advertisements come from) but so has every guerrilla movement, including, as Derfner notes, Zionist ones.