It's antisemitic for sure. And Jews are a race, religion and nation depending on context.

Ashkenazi and Sephardic are races. The Jewish nation are all Jews. Either way, it'd be racist, not just antisemitic, to insult them for being Jewish.

Attacking Jewish people based solely on their religion or nation with no real basis for it, would be antisemitic.

Yes, Jews can be a race.. A Semitic one.