An internal investigation in the Labour Party, which was leaked, concluded that some of its staff, who opposed Corbyn, weaponized accusations of antisemitism so as to ensure the party would not win an election under Corbyn. The mainstream media did its best to support that campaign.

Part of the campaign was to demand a zero-tolerance approach to eliminating antisemitism from the party. A zero-tolerance approach to enforcing any rule tends to create dissention and hostility, because it means that very small differences in conduct lead to enormously different treatment.