I started reading That's Funny. Cohen called himself an anti-Zionist Zionist because he said that Zionism is both racist and anti-racist. To understand that, I suggest you read it because it is a very deep book (which you can read online from the link).
Steve was a socialist and a campaigner against all racism, including antisemitism.
Steve was the author of “That’s Funny You Don’t Look Antisemitic”, published in 1984 and re-published by Engage in 2005. This was a landmark argument against antisemitism on the left.
Steve also wrote this memorable and angry response to a boycott motion passed by the old Higher Education trade union NATFHE in 2006.