Turning a military action into a political talking point is sad.  Every day the US is involved in the fights with our enemies. Our military die in many of the battles.  To pick out a single death and claim the president is responsible  is to blatantly play politics over the responsibilities of the president.  
The death of any American serving the country is unfortunate.  Playing Monday Morning Quarterdeck does not change the decisions that were made or alter how decisions in the future have to be made.  It is impossible to  defeat ISIS or any other enemy and not have casualties.