According to a recent study, if all Americans were vegan, we would reduce our annual agricultural carbon emissions from 623 million tons to 446 million tons. In other words, adopting this lifestyle improves the environment.
However, veganism should be a rather moral position, especially because of the treatment given to animals, rather than a position that aspires to proselytize. The reason is simple: being vegetarian and vegan is so difficult that 84% of those who try, give up.
Agricultural emissions represent only 9% of our total carbon footprint, that is, adopting veganism helps, but does not help too much (especially if in countries like China the increase in emissions is almost exponential). But the fundamental problem is not that, but it is too ambitious to aspire to be all vegans.
Quite simply, given the rate of abandonment, the number of vegans who are occasionally tempted or the number who never stop wanting to eat meat again (and the percentage of people who are not even willing to be vegan), arguing that veganism is a greener diet (in the metaphorical sense) is not only inaccurate, but as unproductive as trying to put out a forest fire with glasses of water.
Abstract ideas about how we will reduce our carbon footprint are not powerful enough to overcome the aroma of grilled steak, especially in a country as meat-centric as the United States.
Ethical dilemmas, then, are a more powerful incentive for many vegans, but not enough for most people (at least for now): only 2% of Americans, for example, are vegans.
If reducing the carbon footprint were an important element of veganism, there would be more incentives to take this position. But the point is, it’s not. In any case, if we reduce the future of the planet (whether ethically or environmentally) to the effectiveness of media passages, awareness campaigns and so on, it is clear that the road will be long, and perhaps unsuccessful.
Given all this, and that awareness and willpower are not up to the task, perhaps we should bet on technological solutions: such as in vitro-conceived meat, meat-flavoured vegetables, painless animals or biotechnological solutions to reduce the impact of our stay on Earth (these days, for example, it was announced how a molecule could eat plastic from the oceans in order to avoid that we all adopt a lifestyle without the use of plastic).