Let us be grateful for small mercies. Thank you Twitter for banning political advertising. Given that such advertising is by its nature biased, tendentious and hard to check, Twitter is behaving as a good publisher should. Politicians may make full use of its outlet. That is democracy. But as the organisation’s chief, Jack Dorsey, points out, with social media awash in “micro-targeting, deepfakes, manipulated videos and misinformation”, those who control it should keep it as clean as possible. Money may not buy truth, but it should not drown fairness.