O n Monday night, Jews will gather outside the London Palladium to protest a performance by veteran rock star Roger Waters. The Campaign Against Antisemitism is calling on the theatre and its owner, Andrew Lloyd Webber, to deny Waters use of the venue. That is, to cancel him. I don’t share this aim. Not because I doubt that Waters is – to quote Polly Samson, wife and lyricist of Waters’ former Pink Floyd bandmate David Gilmour – “antisemitic to [his] rotten core”. I think exactly that. Rather, because I also think there should be a very high bar to cancel...