Malcolm Gladwell wrote his seminal book ‘The Tipping Point’ almost two decades ago.1 In it, he suggested that for an idea to reach critical mass, three rules need to be met. First, people with ‘rare social gifts’ need to be involved and these include charismatic people with large social networks who share important information. Second, the idea needs to have ‘stickiness’—an impact that makes it memorable, and lastly, environmental factors have to be favourable. Those of us who have lived and worked through the tobacco smoking story will remember leading figures who challenged society’s perception of the habit and championed the …