Imo excuse there is no excuse, ever, for:
singling someone out due to their religion, nationality, ethnicity, political opinions and then
inciting a mob to shout at that person until he is driven from the venue.
It is particularly awful when that person is Jewish because of the general persecution they face, but it’s still bad even if it’s just someone disagreeing with you politically. We live in a pluralistic democracy, we can’t persecute people for disagreeing with us.