If you repeat a lie often enough, it becomes the truth.
The origin of this quote is often contested - Lenin, Hitler, Goebbels, Bush (Jr), and JFK all being cited. But regardless of who said it, today's perfect storm of celebrity culture and mass media (including social media) makes such quotes truer than ever (thanks in no small part to tribal instinct, confirmation bias, and the backfire effect).
We might immediately think of our personal political bête noire, but we should not fool ourselves that they're the only one. Governments and oppositions around the world employ the same tactic: tell the same lie to enough people, and it becomes impossible to refute.
Vegans might also think of the meat and dairy industries, with their lies about "happy" cows, "humane" farming, the health "risks" of soya, and our "need" for animal products. But we should ensure that we look within our movement too...
The harm that animal agricultures causes to animals, the environment, global food security, and human health is irrefutable. But when we exaggerate the benefits of a plant-based approach, or resort to superstition and pseudoscience, we risk doing more harm than good. Once someone with a louder voice refutes such claims, it casts doubts on any other more valid claims. And we do not have the loudest voices.
Furthermore, when we make generalisations based on our own experiences, or adopt tactics that appeal to us personally, we might attract those who are similar. But we can alienate those from different backgrounds - and again risk doing more harm than good.
And when we claim that our way is most "effective" without supporting evidence, long-term analysis, or acknowledgement of the limitations of such claims, we risk wasting the efforts of other advocates who adopt our approach.
As Goebbels is alleged to have continued, "The lie can be maintained only for such time as the State can shield the people from the political, economic and/or military consequences of the lie. It thus becomes vitally important for the State to use all of its powers to repress dissent, for the truth is the mortal enemy of the lie, and thus by extension, the truth is the greatest enemy of the State."
As a movement dedicated to uncovering an uncomfortable truth, we certainly should not be expending our efforts to protect our "lies". Therefore, it is only by the adoption of a rational and inclusive approach to vegan advocacy that we can maximise the growth of the movement, and the number of animals spared.