Though the Arabs are Semites the term Anti Semitic strictly applies only to Jews..I will attempt to briefly explain why and then you will understand it.
In the mid 1800’s there was a professor of history..Fredric Shlagel , who wrote a series of papers on languages -Semitic -Hametic…kushateck-Ural Altec etc etc. he was strictly talking about language groups & language groups only but was misunderstood to be speaking instead about races instead. The question still appears in todays circles whether he referring to race or languages. I say it was languages,because he was married to the periods most celebrated Jewish philosophers daughter ”Moses Mendelsohn”and it is highly unlikely that he was referring to race..However the term Semitic became noted to mean Jews .
Then at that same time period there was an actor , an Ex jew a convert to Christianity ‘ Wilhelm Marr” who started an Anti Semitic club of Hamburg a Jew hating club and the ”term Anti Semitic ”was first coined , it strictly meant Anti Jewish hating and that’s all.like I said earlier though Arabs are Semites the term in no way applied to them..it like when an Italian said in past years that that don’t hire anyone whose name ends in a vowel, Japanese among other groups names ends in vowel but that phrase strictly Italians and this phrase “Anti Semitic only applies for Jews and Jews only as the above history that I just presented explains. That is the meaning of their term ANTI SEMITISM and now you know!