If you make a living politicking that means the status quo must be maintained at ALL COST, by any means necessary-in their eyes anyway. These are establishment politicians exploiting this for their own gain and status.
Personally I think this was an Iran-Contra type arms smuggling scheme. The skeleton crew at the embassy was to facilitate arms deals with the favored side in Syria which also has al-Qaeda ties. So to cover up an arms deal with political ramifications domestically & internationally justice and proper closure for those killed will be delayed.