Russia could have sent material directly but that would have implicated them directly in Assad's war. In 2013, Russia wasn't as hands on as it would be a few ye

Russia could have sent material directly but that would have implicated them directly in Assad's war. In 2013, Russia wasn't as hands on as it would be a few years later, trying to keep a bit of distance from his atrocities would have been reasonable. I do admit there are other possible clients for explosive material in the area.