A thing to know about Daesh is they see the BM-21 ‘Grad’ rocket as primarily an artillery weapon and only secondarily as a terror weapon. As witness their use of the rockets against Iraqi forces moving on Mosul.

Well, two can play that game:

US Soldiers loading shells to pick off IS rocket launchpads at their Fire Base around Makmour. pic.twitter.com/HyBIlACbsv

— Beyond The Levant (@TheRealBTL) March 24, 2016