" In some places, daeshi has come to be used as a derogatory adjective referring to "a bigot who imposes their views." And the Free Syrian Army has exploited this homophone in some punning slogans, to convey something like "the Free Syrian Army is stepping on Daesh and on Assad." " Taken from the link.
Also here's a little video to watch if you want.
(Caution The video Has some disturbing content.)