The response to Foley’s beheading should have been a MOAB dropped on an ISIS-held town.MOAB is the acronym for a "massive ordinance air blast," in other words a very big conventional explosive detonated above ground. It is also known as the "mother of all bombs."
Chances are a MOAB blast wave would kill anyone in the open and collapse buildings atop everyone indoors. Humanitarians would decry it as "disproportional." Ask the Japanese how effective Truman's disproportional bombs were.