To make it clear up top, this has nothing to do with NBA superstar Zion Williamson. We wish him the best in all endeavors, and we hope he comes to the Knicks one day (also "Being A Fan Of The Knicks" will probably one day be an antisemitic dog whistle.)

In antisemitic rhetoric, Zionist is often employed as code for ‘Jew’. 

It may appear to refer to supporters of the movement for the establishment/maintenance of a Jewish homeland in Israel, but it frequently serves as cover for promoting harmful stereotypes and conspiracy theories. Simply put, certain users are taking a seemingly-nuanced phrase and laundering antisemitism under the guise of legitimate political discourse, which sucks.

In some instances, "Zionist" is a codeword that alleges Jewish control over global politics, media, and finance. This usage dates back to the beginning of the modern Zionist political movement in the mid-19^th century, intensifying with the publishing of the Protocols of the Learned Elders of Zion (basically the ‘Rosetta Stone’ of modern antisemitic conspiracy theory). Several editions of The Protocols were called “The Zionist Protocols” and were falsely ascribed to early Zionist figures. In America, such usage was popularized by Henry Ford, who published articles inspired by The Protocols that employed “Zionist” extensively throughout (to implicate Jews in various alleged conspiracies). Personally, we think this is mainly because "Zionist" is fun to say and sounds cool, but we're not sure if that's anyone’s official stance. We’re just riffing.

Another reason “Zionist” became code for “Jew,” particularly on the left, is that public awareness of antisemitism and its consequences, post-Holocaust, was higher – and in progressive circles, being openly antisemitic was unacceptable. 

Referring to Zionists, however, somehow made everything kosher. People would claim they were 100% opposed to racism and antisemitism before they declared the need to attack (whether verbally or otherwise) the Zionists. 

By invoking the term, users seek to tap into existing prejudices and fears, casting Jewish individuals as secretive puppeteers behind various societal ills. And it's effective, because have you ever met a normal person into puppeteering?