The story: As Iran and the US are locked in dispute over which sanctions must be lifted, Tehran is moving to publicize its negotiating position. In a PR offensive, the official website of Iran’s supreme leader has released what it describes as a “documentary” on the country’s stance on the Joint Comprehensive Plan of Action (JCPOA).

The 52-minute ‘Definitive Stance’, released on Apr. 8, features an array of top politicians and diplomats from across the political spectrum. Their messages...