One simple answer.
Satan knows that Christ is coming back to rule the Jews at His second coming. Satan knew that Christ was going to be born through the lineage. Satan knew that his defeat comes when all things are fulfilled and so if he can annihilate Israel then Jesus isn’t going to be able to come back and rule from David’s throne. Pretty important stuff to say the least if you’re Satan.
So the attempts have never stopped. All the way through the Bible and history, Satan has tried to rid the world of the chosen line which Christ came and will rule over in the Millennium.
In Revelation his greatest attempt is to act as their Messiah through the antichrist and sign a peace treaty to lull them to sleep. Then break the treaty and try to kill them all.
However, Christ will come back and rule and reign.
To continue on with Zechariah 14 which we spoke of yesterday:
Zechariah 14:6-9 – 6 On that day there will be no light, no cold or frost. 7 It will be a unique day, without daytime or nighttime—a day known to the LORD. When evening comes, there will be light.
8 On that day living water will flow out from Jerusalem, half to the eastern sea and half to the western sea, in summer and in winter.
9 The LORD will be king over the whole earth. On that day there will be one LORD, and his name the only name.
So if you want to know why constantly throughout history the Jews have been a target of anti-Semitism, you don’t have to go any further than Satan himself.