Twitter, which has spent most of Donald Trump’s presidency avoiding a public stand on his use of the medium, has slapped a “public interest notice” on his tweets about the rioting that is occurring in the US in the wake of the violent death in police custody of a black man, George Floyd. According to Twitter, Trump warranted this notice on the grounds that his tweets violate its rules regarding the glorifying of violence. Yet Twitter has nothing to say about the tweets of Iran’s Supreme Leader Ali Khamenei, whose violent posts include hate speech and antisemitism and openly incite rioting and killing. Ted Cruz has called for the launch of a criminal investigation into Twitter’s violation of US sanctions against Iran.